Reduced pressure treatment system

ABSTRACT

A wound treatment appliance is provided for treating all or a portion of a wound. In some embodiments, the appliance comprises a cover or a flexible overlay that covers all or a portion of the wound for purposes of applying a reduced pressure to the covered portion of the wound. In other embodiments, the wound treatment appliance also includes a vacuum system to supply reduced pressure to the site of the wound in the volume under the cover or in the area under the flexible overlay. Methods are provided for using various embodiments of the invention.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.12/941,390, filed on Nov. 8, 2010, which is a continuation-in-part ofU.S. application Ser. No. 12/719,715, filed on Mar. 8, 2010, now U.S.Pat. No. 8,303,552, which is a continuation of U.S. application Ser. No.11/098,203, filed on Apr. 4, 2005, now U.S. Pat. No. 7,708,724, whichclaims the benefit of U.S. Application No. 60/559,727, filed on Apr. 5,2004, each of which is incorporated herein by reference in its entirety.U.S. application Ser. No. 12/941,390 is also a continuation-in-part ofU.S. application Ser. No. 11/064,813, filed on Feb. 24, 2005, now U.S.Pat. No. 8,062,272, which claims the benefit of U.S. Application No.60/573,655, filed on May 21, 2004, each of which is incorporated hereinby reference in its entirety. U.S. application Ser. No. 12/941,390 isalso a continuation-in-part of U.S. application Ser. No. 11/098,265,filed on Apr. 4, 2005, now U.S. Pat. No. 7,909,805, which is acontinuation-in-part of U.S. application Ser. No. 11/064,813, filed onFeb. 24, 2005, now U.S. Pat. No. 8,062,272, and which claims the benefitof U.S. Application No. 60/559,727, filed on Apr. 5, 2004, each of whichis incorporated herein by reference in its entirety.

BACKGROUND OF THE INVENTION

The present invention generally relates to treatment of wounds, and morespecifically to improved apparatus and methods for treating a wound or aportion of a wound on a body by applying reduced pressure to the body atthe site of the wound. In this context, the terms “wound” and “body” areto be interpreted broadly, to include any wound, body, or body part thatmay be treated using reduced pressure.

The treatment of open or chronic wounds that are too large tospontaneously close or otherwise fail to heal by means of applyingreduced pressure to the site of the wound is well known in the art. Onesuch system is disclosed in U.S. patent application Ser. No. 10/652,100,which was filed with the U.S. Patent and Trademark Office on Aug. 28,2003 and published as U.S. Publication No. 2004/0073151 A1. Thedisclosure of this U.S. patent application is incorporated herein byreference. Another system is disclosed in U.S. patent application Ser.No. 11/026,733, entitled “Improved Reduced Pressure Wound TreatmentAppliance,” which was filed with the U.S. Patent and Trademark Office onDec. 30, 2004, now U.S. Pat. No. 7,128,735. The disclosure of this U.S.patent application is also incorporated herein by reference. Yet anothersystem is disclosed in U.S. patent application Ser. No. 11/064,813,entitled “Improved Flexible Reduced Pressure Wound Treatment Appliance,”which was filed with the U.S. Patent and Trademark Office on Feb. 24,2005 and published as U.S. Publication No. 2005/0261642 A1. Thedisclosure of this U.S. patent application is also incorporated hereinby reference.

Reduced pressure wound treatment systems currently known in the artcommonly involve placing a treatment device that is impermeable toliquids over the wound, using various means to seal the treatment deviceto the tissue of the patient surrounding the wound, and connecting asource of reduced pressure (such as a vacuum pump) to the treatmentdevice in a manner so that an area of reduced pressure is created underthe treatment device in the area of the wound. The systems alsotypically act to remove exudate that may be aspirated from the wound.Thus, such systems also typically have a separate collection devicelocated between the reduced pressure source and the treatment device tocollect. This collection device represents a separate source of expensein reduced pressure wound treatment. In addition, it is advantageous insome circumstances to remove exudate from the wound so that the exudatedoes not remain in the presence of the wound. For example, healing ofthe wound may be enhanced by the removal of exudate from the wound insome circumstances. In yet other cases, it may be advantageous to beable to gain physical access to the wound without having to remove thetreatment device from the body surrounding the wound. For example, itmay be desirable to monitor or treat the condition of the wound duringthe treatment process. If the treatment device is sealed to the bodyusing an adhesive tape, removing the adhesive tape to monitor or treatthe wound may cause discomfort and pain for the patient.

Therefore, there is a need for a wound treatment device that caneliminate the requirement for a separate collection device to collectexudate from the wound. This type of device could reduce the expenseinvolved in wound treatment by eliminating the need for the collectiondevice. There is also a need for such a treatment device to removeexudate from the presence of the wound to aid in wound healing. It mayalso be desirable for this type of treatment device to be disposable incertain circumstances. Further, there is a need for a treatment devicethat would allow for physical access to the wound without the need forremoving the treatment device from the body. This type of device couldenhance patient comfort. In addition, where the access is simple andquickly obtained, it could also decrease the cost of wound treatment byreducing the time required of healthcare practitioners to be involved inwound treatment. Finally, there is also a need for a reduced pressuretreatment system that is relatively inexpensive, while meeting the needsdescribed above.

Reduced pressure wound treatment systems currently known in the art alsocommonly involve placing a cover that is impermeable to liquids over thewound, using various means to seal the cover to the tissue of thepatient surrounding the wound, and connecting a source of reducedpressure (such as a vacuum pump) to the cover in a manner so that anarea of reduced pressure is created under the cover in the area of thewound. However, the covers currently known and used in the art have anumber of disadvantages. For example, in one version they tend to be inthe form of a flexible sheet of material that is placed over the woundand sealed to the surrounding tissue using an adhesive, adhesive tape,or other similar means. As tissue swelling in the area of the wounddecreases during the healing process, the adhesive may begin to stretchthe surrounding tissue, as well as tissue within the wound, resulting indiscomfort and pain to the patient. This may necessitate more frequentcover changes, increasing the time medical staff must expend in treatingthe wound. This additional time, of course, also tends to increase theexpense involved in treating the wound. In addition, these types ofcovers can typically only be used where there is normal tissue adjacentto the wound to which the adhesive seal can be attached. Otherwise, theseal must be made in a portion of the area of the wound, and exudatefrom the wound tends to break the seal so that reduced pressure cannotbe maintained beneath the wound cover. Thus, such covers (and many othercovers requiring adhesive seals) may typically only be used to treat anentire wound, as opposed to only a portion of a wound. Further, theadhesive seal creates discomfort for the patient when the sheet cover isremoved. In other versions, the covers tend to be rigid or semi-rigid innature so that they are held away from the surface of the wound. Inthese versions, the covers are sometimes difficult to use because theshape and contour of the patient's body in the area of the wound do notreadily adapt to the shape of the cover. In such cases, additional timeis required for the medical staff to adapt the cover for its intendeduse. This also increases the expense of wound treatment. In addition, itis also often necessary to use an adhesive, adhesive tape, or othersimilar means to seal the rigid or semi-rigid cover to the tissuesurrounding the wound. In these instances, the same disadvantagesdiscussed above with respect to the first version also apply to thisversion as well. In still other cases, the rigid and semi-rigid coversmust be used with padding in the area where the cover is adjacent to thepatient to prevent the edges of the cover from exerting undue pressureon the tissue surrounding the wound. Without the padding, the patientmay experience pain and discomfort. The additional padding, which maymake the cover itself more expensive, may also take a greater amount oftime to place on the patient for treatment purposes. These covers mayalso have the problem of placing tension on the surrounding tissue asthe swelling in the area of the wound decreases during the healingprocess. In yet another version, covers are constructed of combinationsof flexible materials and rigid materials. In these versions, a flexiblemember, such as a flexible sheet, is typically supported by a rigid orsemi-rigid structure that is either placed between the flexible memberand the wound or in the area above and outside the flexible member. Ineither case, the flexible member must usually be sealed to the tissuesurrounding the wound using an adhesive, adhesive tape, or other similarmeans. This seal creates the same problems described above. In addition,the same problems described above with respect to rigid and semi-rigidstructures are also often present. In all of the versions describedabove, it may be difficult to tell if reduced pressure in the area ofthe wound under the cover has been lost because the cover itself doesnot generally provide a visual clue of such loss.

Therefore, there is a need for a reduced pressure wound treatment systemthat has a means to enclose all or a portion of a wound without the needfor an adhesive seal. There is also a need for such enclosing means tobe flexible, so that it adapts to changing shapes and contours of thepatient's body as wound healing progresses. Further, there is a need foran enclosing means that is adaptable to a wide variety of patient bodyshapes and contours. There is also a need for an enclosing means that issimple to apply to the patient's body, and simple to remove from thepatient's body. Such enclosing means would also take less time to applyand remove, reducing the expense involved in wound treatment. There isalso a need for an enclosing means that is relatively inexpensive, whilemeeting the needs described above. In addition, there is a need for anenclosing means that may be used within the wound (or a portionthereof), without the need to seal the enclosing means to normal tissuesurrounding the wound. Further, there is a need for an enclosing meansthat flexes with movement of the portion of the body surrounding thewound, without the need for an adhesive seal or rigid or semi-rigidstructure. Finally, there is a need for an enclosing means that providesa visual clue of loss of reduced pressure in the area of the wound underthe enclosing means.

SUMMARY OF THE INVENTION

The present invention is directed to reduced pressure treatmentappliances and methods that satisfy the needs described above. Asdescribed in greater detail below, they have many advantages overexisting reduced pressure treatment apparatus and methods when used fortheir intended purpose, as well as novel features that result in newreduced pressure treatment appliances and methods that are notanticipated, rendered obvious, suggested, or even implied by any of theprior art apparatus or methods, either alone or in any combinationthereof.

One embodiment of the present invention is directed to a reducedpressure wound treatment appliance and methods that satisfy the needsdescribed above. As described in greater detail below, they have manyadvantages over existing reduced pressure wound treatment apparatus andmethods when used for their intended purpose, as well as novel featuresthat result in a new reduced pressure wound treatment appliance andmethods that are not anticipated, rendered obvious, suggested, or evenimplied by any of the prior art apparatus or methods, either alone or inany combination thereof.

In accordance with one embodiment, a wound treatment appliance isprovided for treating all or a portion of a wound by applying reducedpressure (i.e., pressure that is below ambient atmospheric pressure) tothe portion of the wound to be treated in a controlled manner for aselected time period in a manner that overcomes the disadvantages ofcurrently existing apparatus. The application of reduced pressure to awound provides such benefits as faster healing, increased formation ofgranulation tissue, closure of chronic open wounds, reduction ofbacterial density within wounds, inhibition of burn penetration, andenhancement of flap and graft attachment. Wounds that have exhibitedpositive response to treatment by the application of negative pressureinclude infected open wounds, decubitus ulcers, dehisced incisions,partial thickness burns, and various lesions to which flaps or graftshave been attached.

In some embodiments, the wound treatment appliance is comprised of animpermeable flexible overlay and reduced pressure supply means, whichare described in more detail below and are used to connect the flexibleoverlay to a reduced pressure supply source that provides a supply ofreduced pressure to the flexible overlay. In some embodiments, theflexible overlay is adapted to be placed over and enclose all or aportion of a wound on the surface of the body of a patient. The flexibleoverlay is also adapted to maintain reduced pressure under the flexibleoverlay in the area of the wound. The flexible overlay collapses in theapproximate direction of the area of the wound to be treated whenreduced pressure is supplied to the volume under the flexible overlay inthe area of the wound. This collapse causes the formation of anapproximately hermetic seal (described in more detail below) between theflexible overlay and the body in the area of the wound. In someembodiments, the flexible overlay is further comprised of an interiorsurface facing the area of the wound to be treated, wherein the surfacearea of the interior surface is greater than the surface area of theportion of the body to be enclosed by the flexible overlay. In otherembodiments, the flexible overlay is further comprised of a bottomportion having an approximately elongated conical shape with anapproximately elliptically-shaped open end at the base of the elongatedconical bottom portion. In these embodiments, the approximatelyelliptically-shaped open end at the base is sized to be placed over andenclose the area of the wound to be treated. In yet other embodiments,the flexible overlay (as opposed to only the bottom portion thereof) hasan approximately elongated conical shape having an approximatelyelliptically-shaped open end at its base. In these embodiments, theapproximately elliptically-shaped perimeter of the open end at the baseof the flexible overlay is positioned over all or a portion of the woundon the surface of the body. In some of these embodiments, the flexibleoverlay further comprises a port located approximately at the apex ofthe elongated conically-shaped flexible overlay. In these embodiments,the reduced pressure supply means is operably connected to the port. Inyet other embodiments, the flexible overlay is comprised of at leastthree cover portions, each of such cover portions being approximatelytriangular in shape. One point of each of the at least threetriangular-shaped cover portions are joined to form an apex of theflexible overlay and one side of each at least three triangular-shapedcover portions adjacent to the apex is joined to an adjacent side ofanother of such at least three triangular-shaped cover portions so thatthe bases of the at least three triangular-shaped cover portions form anopening sized to be placed over and enclose the area of the wound to betreated. In some of these embodiments, the flexible overlay is furthercomprised of a port located approximately at the apex of the flexibleoverlay and the reduced pressure supply means is operably connected tothe port. In yet other embodiments, the flexible overlay may becup-shaped. In still other embodiments, at least one fold forms in thesurface of the flexible overlay when it collapses, so that fluidsaspirated by the wound flow along the at least one fold to the reducedpressure supply means, where they are removed from the flexible overlayby means of the reduced pressure supply means cooperating with thereduced pressure supply source. In other embodiments, the flexibleoverlay is further comprised of suction assist means, which assist inthe application of reduced pressure to the area of the wound and removalof exudate from the wound. In some of these embodiments, the suctionassist means may be channels disposed in, or raised portions disposedon, the surface of the flexible overlay. In other embodiments, theappliance further comprises supplemental sealing means, which aredescribed in more detail below, to form a seal between the flexibleoverlay and the body in the area of the wound. In yet other embodiments,the appliance further comprises a suction drain and suction drainconnecting means, which are described in more detail below, to operablyconnect the reduced pressure supply means to the suction drain so thatthe suction drain is in fluid communication with the reduced pressuresupply means and reduced pressure is supplied to the volume under theflexible overlay in the area of the wound by means of the suction drain.The suction drain extends from the reduced pressure supply means intothe volume under the flexible overlay in the area of the wound.

In some embodiments, the wound treatment appliance is comprised of awound treatment device and a vacuum system. In some embodiments, thevacuum system is further comprised of a reduced pressure supply sourcethat provides a supply of reduced pressure and reduced pressure supplymeans to operably connect the wound treatment device to the reducedpressure supply source, so that the volume under the wound treatmentdevice in the area of the wound is supplied with reduced pressure by thereduced pressure supply source. In various embodiments, the woundtreatment device and the reduced pressure supply means may generallyhave substantially the same structure, features, characteristics andoperation as the appliance described above in connection with otherembodiments previously described.

In some embodiments, the reduced pressure supply source is comprised ofa vacuum pump. In some of these embodiments, the reduced pressure supplysource further comprises a control system for the vacuum pump, whereinthe control system may control at least the level of suction produced bythe vacuum pump or the rate of fluid flow produced by the vacuum pump,or any combination of rate of suction and rate of fluid flow of thevacuum pump. In other embodiments, the reduced pressure supply sourcefurther comprises a filter operably positioned between the vacuum pumpand the reduced pressure supply means. In these embodiments, the filterprevents the venting of and contamination of the vacuum pump bymicro-organisms aspirated from the wound or fluids aspirated from thewound or both. In yet other embodiments, the vacuum pump is comprised ofa portable vacuum pump. In still other embodiments, the reduced pressuresupply means is comprised of flexible tubing. In other embodiments, thereduced pressure supply means is further comprised of a collectionsystem that is operably positioned between the wound treatment deviceand the reduced pressure supply source. In some of these embodiments,the collection system comprises a container to receive and hold fluidaspirated from the wound and pressure halting means to halt theapplication of reduced pressure to the wound when the fluid in thecontainer exceeds a predetermined amount. In other embodiments, thereduced pressure under the flexible overlay in the area of the wound isin the range from approximately 20 mm of Hg below atmospheric pressureto approximately 125 mm of Hg below atmospheric pressure. In yet otherembodiments, the reduced pressure is applied in a cyclic nature, thecyclic nature providing alternating time periods of application ofreduced pressure and without application of reduced pressure. In someembodiments, the wound treatment appliance further comprises tissueprotection means, which are described in more detail below, to protectand strengthen the body tissue that is adjacent to the flexible overlayat the wound site. In some of these embodiments, the tissue protectionmeans is a hydrocolloid material.

In some embodiments, the wound treatment appliance is comprised of awound treatment device, a vacuum system, and wound packing means, whichare described in more detail below, that are positioned between thewound treatment device and the portion of the wound to be treated. Invarious embodiments, the wound treatment device and the vacuum systemmay generally have substantially the same structure, features,characteristics and operations as the wound treatment device and thevacuum system, respectively, described above in connection with theother embodiments of the invention. In some embodiments, the flexibleoverlay of the wound treatment device is placed over all or a portion ofthe wound and the wound packing means when the flexible overlay ispositioned on the surface of the body at the wound site. In someembodiments, the wound packing means is comprised of absorbentdressings, antiseptic dressings, nonadherent dressings, water dressings,or combinations of such dressings. In some embodiments, the woundpacking means is preferably comprised of gauze or cotton or anycombination of gauze and cotton. In still other embodiments, the woundpacking means is comprised of an absorbable matrix adapted to encouragegrowth of the tissue in the area of the wound under the flexible overlayinto the matrix. The absorbable matrix is constructed of an absorbablematerial that is absorbed into the epithelial and subcutaneous tissue inthe wound as the wound heals. Because of the absorbable nature of theabsorbable matrix, the matrix should require less frequent changing thanother dressing types during the treatment process. In othercircumstances, the matrix may not need to be changed at all during thetreatment process. In some embodiments, the absorbable matrix iscomprised of collagen or other absorbable material. In some embodiments,the appliance further comprises a suction drain and suction drainconnecting means, which are described in more detail below, to operablyconnect the reduced pressure supply means to the suction drain so thatthe suction drain is in fluid communication with the reduced pressuresupply means and reduced pressure is supplied to the volume under theimpermeable flexible overlay in the area of the wound by means of thesuction drain. In these embodiments, the suction drain extends from thereduced pressure supply means into the volume under the impermeableflexible overlay in the area of the wound. In some embodiments, thesuction drain is further comprised of a distal end portion and thedistal end portion has at least one perforation in the surface thereof.In some embodiments, the distal end portion of the suction drain ispositioned within the interior volume of the wound packing means.

In some embodiments, the wound treatment appliance is comprised of awound treatment device and a vacuum system. In various embodiments, thewound treatment device is comprised of an impermeable flexible overlayand a seal. The impermeable flexible overlay is sized to be placed overand enclose the area of the wound to be treated and is adapted tomaintain reduced pressure in the area of the wound to be treated. Theseal seals the impermeable flexible overlay to the body in the area ofthe wound in a manner so that reduced pressure is maintained under theimpermeable overlay in the area of the wound to be treated. In addition,in various embodiments of the invention, the vacuum system is comprisedof a suction bulb, which may (but not necessarily) provide a source ofreduced pressure, and reduced pressure supply means, which are describedin more detail below, to operably connect the impermeable flexibleoverlay to the suction bulb, so that the area of the wound under theimpermeable flexible overlay may be supplied with reduced pressure bythe suction bulb. In some embodiments, the flexible wound cover may becomprised of a flexible overlay that has substantially the samestructure, features, characteristics and operation as the flexibleoverlay described above in connection with other embodiments. In someembodiments, the suction bulb is further comprised of an inlet port andan outlet port, wherein the inlet port is operably connected to thereduced pressure supply means, and the vacuum system further comprisesan exhaust tubing member operably connected to the outlet port. In someembodiments, the vacuum system further comprises an exhaust controlvalve operably connected to the exhaust tubing member. In otherembodiments, the vacuum system is further comprised of a filter operablyconnected to the exhaust tubing member, which prevents the venting ofmicro-organisms aspirated from the wound or fluids aspirated from thewound or both. In yet other embodiments, the vacuum system is furthercomprised of a supplemental vacuum system that is operably connected tothe exhaust tubing member. In these embodiments, the supplemental vacuumsystem may generally have substantially the same structure, features,characteristics and operation as the vacuum system described above inconnection with other embodiments of the invention.

Another embodiment involves a method of treating a wound on a body. Inone embodiment, the method comprises the following steps. First,positioning a flexible overlay on the body over the area of the wound tobe treated, wherein the flexible overlay is sized to be placed over andenclose the area of the wound to be treated and adapted to maintainreduced pressure in the area of the wound to be treated. Second,operably connecting the flexible overlay with a vacuum system forproducing reduced pressure in the volume under the flexible overlay inthe area of the wound to be treated. Third, collapsing the flexibleoverlay in the approximate direction of the wound when reduced pressureis supplied to the volume under the flexible overlay in the area of thewound so that an approximately hermetic seal (described in more detailbelow) is formed between the impermeable flexible overlay and the bodyin the area of the wound. Fourth, maintaining the reduced pressure untilthe area of the wound being treated has progressed toward a selectedstage of healing.

In other embodiments, the method further comprises the step of placingtissue protection means on the tissue of the body that is to beapproximately adjacent to the flexible overlay, such step beingperformed prior to positioning the flexible overlay over the area of thewound to be treated. The tissue protection means, which is described inmore detail below, protects and strengthens the tissue of the bodyadjacent to the flexible overlay at the wound site. In yet otherembodiments, the method further comprises the step of placing woundpacking means (described in more detail above) between the wound and theflexible overlay in the area of the wound to be treated, such step beingperformed prior to positioning the flexible overlay over the area of thewound to be treated. In still other embodiments, the vacuum system iscomprised of a suction bulb and the method further comprises the step ofsqueezing the suction bulb to reduce its volume and then releasing thesuction bulb, so that reduced pressure is produced in the volume underthe flexible overlay in the area of the wound. In other embodiments, thereduced pressure under the impermeable overlay in the area of the woundis in the range from approximately 20 mm of Hg below atmosphericpressure to approximately 125 mm of Hg below atmospheric pressure. Instill other embodiments, the reduced pressure is applied in a cyclicnature, the cyclic nature providing alternating time periods ofapplication of reduced pressure and without application of reducedpressure.

As is illustrated in the detailed descriptions herein, embodiments ofthe wound treatment appliance of the present invention meet the needsdiscussed above in the Background section. For example, in oneembodiment of a flexible overlay having a bottom portion with anapproximately elongated conical shape, the flexible overlay is placedover and encloses all or a portion of the wound. When the flexibleoverlay is enclosing all or a portion of the wound, the portions of theflexible overlay positioned adjacent to the surface of the body at thewound site are at (or can be deformed to be at) a relatively acute anglerelative to such surface of the body. When reduced pressure is appliedto the area under the flexible overlay, the flexible overlay is drawndownward, collapsing the flexible overlay in the approximate directionof the wound. As the flexible overlay collapses, the portions of theflexible overlay adjacent to the perimeter of the opening of theflexible overlay are drawn tightly against the surface of the body atthe wound site, thus forming an approximately hermetic seal. Referencesto an “approximately hermetic seal” herein refer generally to a sealthat is gas-tight and liquid-tight for purposes of the reduced pressuretreatment of the wound. It is to be noted that this seal need not beentirely gas-tight and liquid-tight. For example, the approximatelyhermetic seal may allow for a relatively small degree of leakage, sothat outside air may enter the volume under the flexible overlay in thearea of the wound, as long as the degree of leakage is small enough sothat the vacuum system can maintain the desired degree of reducedpressure in the volume under the flexible overlay in the area of thewound. In some uses where the collapsing flexible overlay may notproduce an approximately hermetic seal that is solely capable ofmaintaining the reduced pressure in the volume under the impermeableoverlay in the area of the wound, it may be necessary to providesupplemental sealing means, which are described in more detail below,and which are used to provide a seal between the portions of theflexible overlay and the body where the approximately hermetic seal isnot adequate. As a result, the flexible overlay is simple to apply tothe patient. There is also often no need for any other sealing means inmost cases, which means that there is usually no need for medical staffto take the time to make a separate seal. Even where the geometry of thesurface of the body surrounding the wound may require that supplementalsealing means be used to provide some limited assistance to ensure aseal, the amount of such assistance (such as by applying an adhesive) islimited, especially when compared to current covers in the art. Inaddition, as swelling of tissue at the wound site decreases, theflexible nature of the flexible overlay allows it to further deform toconform to the changing shape and contours at the wound site. Thisprevents the patient from being discomforted as the swelling decreases.It also reduces the need to change the covering over the wound ashealing progresses. This is generally not true in cases involvingflexible, semi-rigid and rigid covers that exist in the art. Forexample, even where semi-rigid and rigid covers do not utilize anadhesive seal and rely solely upon the reduced pressure to hold them inplace, they do not generally change shape enough to flex withsubstantial changes in the shape and contour of the surrounding bodysurface. Thus, they may not be appropriate for use with body portionsthat are subject to such changes, while the flexible nature of theflexible overlay, along with its increased surface area that can bendand flex, allow it to be used in such circumstances without the need foran adhesive seal. In the same way, the flexible overlay may generally beused for unusual geometries of the body at or surrounding the woundbecause of the overlay's flexible nature and relatively large surfacearea. In contrast, flexible sheets and semi-rigid and rigid covers mayrequire substantial modification and means to provide an adequate seal.In addition, such covers may require that the patient be partially orwholly immobilized during the treatment process to avoid movement in thearea of the body surrounding the wound to avoid breaking the seal. Andsuch covers must usually be sealed to normal tissue surrounding thewound. The flexible overlay, however, may be used within the perimeterof a wound in many cases because there is not typically a need to sealthe flexible overlay to normal tissue surrounding the wound. Further,because there is typically no need for an adhesive seal, removal of theflexible overlay merely requires removal of the reduced pressure fromthe area under the flexible overlay. It is thus simple to remove fromthe patient. For this reason, it will tend to reduce the time requiredof medical staff for wound treatment, which will also tend to reduce thecost of wound treatment.

In addition, there is no pain and discomfort for the patient when theflexible overlay is removed. Even if a limited amount of supplementalsealing means (such as an adhesive) are required to provide a seal at aportion of the flexible overlay that is adjacent to the surfacesurrounding the wound, the reduced amount of supplemental sealing meanswill cause a corresponding reduction in the amount of such pain anddiscomfort. Further, some embodiments of the collapsed flexible overlaywill have folds in its surface while in the collapsed state, so thatfluid aspirated by the wound may flow along the folds to be removed fromunder the flexible overlay. In some embodiments, the flexible overlay isfurther comprised of suction assist means, which also assist in theapplication of reduced pressure to the area of the wound and removal ofexudate from the wound. In some of these embodiments, the suction assistmeans may be channels disposed in, or raised portions disposed on, thesurface of the flexible overlay. In addition, if reduced pressure islost under the flexible overlay, the flexible overlay will expandoutward from the wound, providing a visual indication that reducedpressure has been lost. Finally, in some embodiments, the flexibleoverlay is relatively inexpensive to manufacture, even though it meetsthe described needs.

In some embodiments, the wound treatment appliance is comprised of afluid impermeable flexible overlay, a collection chamber to receive andhold fluid aspirated from the wound, collection chamber attachment meansto operably attach the collection chamber to the flexible overlay, asdescribed in more detail below, and reduced pressure supply means, whichare described in more detail below. In some embodiments, the flexibleoverlay is adapted to be placed over and enclose all or a portion of thewound. In various embodiments, except as described in more detail below,the flexible overlay has substantially the same structure, featurescharacteristics and operation as the flexible overlay described above inconnection with other embodiments. In addition, in some embodiments, thereduced pressure supply means is used to operably connect the collectionchamber to a reduced pressure supply source that provides a supply ofreduced pressure to the collection chamber, so that the volume withinthe collection chamber and under the impermeable overlay in the area ofthe wound to be treated are supplied with reduced pressure by thereduced pressure supply source. In various embodiments, except asdescribed in more detail below, the reduced pressure supply means toconnect the reduced pressure supply source to the collection chamber inthe embodiments of the invention may have substantially the samestructure, features, characteristics, and operation as the reducedpressure supply means described above in connection with otherembodiments.

In some embodiments, the flexible overlay is attached by collectionchamber attachment means to a collection chamber that receives and holdsfluid aspirated from the wound. In some embodiments, the collectionchamber may be approximately cylindrical in shape. In variousembodiments, the collection chamber attachment means operably attachesthe collection chamber to the flexible overlay in a manner so that thefluid and reduced pressure are permitted to flow between the collectionchamber and the volume under the flexible overlay in the area of thewound. In some embodiments, the collection chamber is positionedapproximately adjacent to the impermeable flexible overlay on the sideof the impermeable flexible overlay opposite the wound and thecollection chamber attachment means is a rigid or semi-rigid connectingmember positioned between the collection chamber and the impermeableflexible overlay. In these embodiments, the connecting member has a porttherein that extends between the collection chamber and the flexibleoverlay. In embodiments where the flexible overlay is approximatelyelongated-conically shaped, the collection chamber and the collectionchamber attachment means may be positioned approximately at the apex ofthe flexible overlay on the side of the impermeable flexible overlayopposite the wound. In some embodiments, the collection chamber may beapproximately cylindrical in shape. In other embodiments, the collectionchamber attachment means may be further comprised of a flow controlmeans, which is described in more detail below, operably positionedbetween the collection chamber and the flexible overlay. In theseembodiments, the flow control means permit the fluid to flow from thevolume under the flexible overlay in the area of the wound into thecollection chamber, but not in the opposite direction. In some of theseembodiments, the flow control means may be comprised of a valve. In someof these embodiments, the valve may be comprised of a flapper-typevalve. In yet other embodiments, the collection chamber is positionedapproximately adjacent to the impermeable flexible overlay on the sideof the impermeable flexible overlay opposite the wound and thecollection chamber attachment means is comprised of a membrane. In theseembodiments, the membrane acts as a barrier separating the collectionchamber and the impermeable flexible overlay, so that the membrane actsas a portion of the surface of the collection chamber and a portion ofthe surface of the impermeable flexible overlay. In addition, themembrane has at least one port therein so that the volume within thecollection chamber is in fluid communication with the volume under theimpermeable flexible overlay in the area of the wound. In embodimentswhere the impermeable flexible overlay has an approximately conicalshape or approximately elongated conical shape, the impermeable flexibleoverlay may have a base end opening and a top end opening opposite thebase end opening. In these embodiments, the base end opening may have aneither approximately circular shape or approximately elliptical shapesized to be placed over and enclose the area of the wound to be treated.The top end opening may have either an approximately circular shape orapproximately elliptical shape. In these embodiments, the membrane issized to be of the same shape and size as the top end opening and themembrane is positioned so that it is attached to the entire perimeter ofthe top end opening and covers the entire top end opening.

In some embodiments, the collection chamber may have an approximatelyconical shape or approximately elongated conical shape with a chamberbottom end opening and a reduced pressure supply port positioned at theapex of the collection chamber opposite the chamber bottom end opening.In various embodiments, the chamber bottom end opening may have aneither approximately circular shape or approximately elliptical shapeadapted to be of approximately the same size and shape as the top endopening of the impermeable flexible overlay. In some of theseembodiments, the perimeter of the chamber bottom end opening is attachedto the membrane in a manner so that the collection chamber is airtight,except for the port in the membrane and the reduced pressure supplyport. The reduced pressure supply port operably connects the reducedpressure supply means to the collection chamber. In some embodiments,the collection chamber attachment means is further comprised of flowcontrol means operably connected with the at least one port, wherein theflow control means permits fluid aspirated from the wound to flow fromthe volume under the impermeable flexible overlay in the area of thewound through the at least one port to the collection chamber, but notin the opposite direction. In some of these embodiments, the flowcontrol means is comprised of a valve. Preferably, this valve iscomprised of a flapper-type valve.

In another embodiment, the wound treatment appliance is comprised of awound treatment device and a vacuum system, which is further comprisedof a reduced pressure supply source that provides a supply of reducedpressure and reduced pressure supply means to operably connect the woundtreatment device to the reduced pressure supply source. In variousembodiments, except as described below, the wound treatment device andthe reduced pressure supply means may generally have substantially thesame structure, features, characteristics and operations as theappliance described above in connection with other embodiments. In theseembodiments, the reduced pressure supply means operably connect thewound treatment device to the reduced pressure supply source so that thevolume within the collection chamber and under the wound treatmentdevice in the area of the wound is supplied with reduced pressure by thereduced pressure supply source.

In some embodiments, the reduced pressure supply source is comprised ofa vacuum pump. In some of these embodiments, the reduced pressure supplysource further comprises a control system for the vacuum pump, whereinthe control system controls the operation of the vacuum pump. In otherembodiments, the reduced pressure supply source further comprises afilter operably positioned between the vacuum pump and the reducedpressure supply means. In these embodiments, the filter prevents theventing of and contamination of the vacuum pump by micro-organismsaspirated from the wound or fluids aspirated from the wound or both. Inyet other embodiments, the vacuum pump is comprised of a portable vacuumpump. In still other embodiments, the reduced pressure supply means iscomprised of flexible tubing. In other embodiments, the reduced pressureunder the flexible overlay in the area of the wound is in the range fromapproximately 20 mm of Hg below atmospheric pressure to approximately125 mm of Hg below atmospheric pressure. In yet other embodiments, thereduced pressure is applied in a cyclic nature, the cyclic natureproviding alternating time periods of application of reduced pressureand without application of reduced pressure. In some embodiments, thewound treatment appliance further comprises tissue protection means,which are described in more detail below, to protect and strengthen thebody tissue that is adjacent to the flexible overlay at the wound site.In some of these embodiments, the tissue protection means is ahydrocolloid material. In still other embodiments, wound packing means,which are described in more detail herein, are positioned between thewound treatment device and the portion of the wound to be treated.

Another embodiment of the present invention involves a method oftreating a wound on a body. In one embodiment, the method comprises thefollowing steps. First, a wound treatment device is positioned on thebody over the area of the wound to be treated, wherein the woundtreatment device is comprised of an impermeable flexible overlay, acollection chamber, and collection chamber attachment means, which aredescribed in more detail below. In this embodiment, the flexible overlayis sized to be placed over and enclose the area of the wound to betreated and adapted to maintain reduced pressure in the area of thewound to be treated. In addition, in this embodiment, the collectionchamber receives and holds fluid aspirated from the wound and thecollection chamber attachment means, which is described in more detailbelow, operably attaches the collection chamber to the impermeableflexible overlay in a manner so that reduced pressure and the fluid arepermitted to flow between the collection chamber and the impermeableflexible overlay. Second, the collection chamber is operably connectedwith a vacuum system for producing reduced pressure in the volume withinthe collection chamber and in the volume under the flexible overlay inthe area of the wound to be treated. Third, the flexible overlay iscollapsed in the approximate direction of the wound when reducedpressure is supplied to the volume under the flexible overlay in thearea of the wound so that an approximately hermetic seal (described inmore detail herein) is formed between the impermeable flexible overlayand the body in the area of the wound. Fourth, reduced pressure ismaintained until the area of the wound being treated has progressedtoward a selected stage of healing.

In other embodiments, the method further comprises the step of placingtissue protection means on the tissue of the body that is to beapproximately adjacent to the impermeable flexible overlay, such stepbeing performed prior to positioning the impermeable flexible overlayover the area of the wound to be treated. The tissue protection means,which is described in more detail below, protects and strengthens thetissue of the body adjacent to the flexible overlay at the wound site.In yet other embodiments of the invention, the method further comprisesthe step of placing wound packing means (described in more detailherein) between the wound and the impermeable flexible overlay in thearea of the wound to be treated, such step being performed prior topositioning the impermeable flexible overlay over the area of the woundto be treated. In still other embodiments, the reduced pressure underthe impermeable overlay in the area of the wound is in the range fromapproximately 20 mm of Hg below atmospheric pressure to approximately125 mm of Hg below atmospheric pressure. In still other embodiments, thereduced pressure is applied in a cyclic nature, the cyclic natureproviding alternating time periods of application of reduced pressureand without application of reduced pressure.

In accordance with one embodiment, a treatment appliance is provided fortreating a wound on a body by applying reduced pressure (i.e., pressurethat is below ambient atmospheric pressure) to the wound in a controlledmanner for a selected time period in a manner that overcomes thedisadvantages of currently existing apparatus. For example, theapplication of reduced pressure to a wound provides such benefits asfaster healing, increased formation of granulation tissue, closure ofchronic open wounds, reduction of bacterial density within wounds,inhibition of burn penetration, and enhancement of flap and graftattachment. Wounds that have exhibited positive response to treatment bythe application of negative pressure include infected open wounds,decubitus ulcers, dehisced incisions, partial thickness burns, andvarious lesions to which flaps or grafts have been attached.

In one embodiment, an appliance for treating a wound on a body iscomprised of a cover, sealing means to seal the cover to the body, whichare described in more detail below, and reduced pressure supply means,which are also described in more detail below. The cover, which is sizedto be placed over and enclose the wound, is further comprised of a topcup member, an interface member, and interface attachment means forremovably attaching the top cup member to the interface member. Theinterface member is further comprised of flow control means that permitexudate from the wound to flow from the wound into the top cup member,but not in the opposite direction. Thus, in this embodiment, theinterface member is sealed to the body by the sealing means and exudatefrom the wound flows from the wound through the flow control means inthe interface member into the volume of the cover above the interfacemember. The flow control means do not allow the exudate to flow backinto the area of the wound under the interface member. The cover and thesealing means allow reduced pressure to be maintained in the volumeunder the cover at the site of the wound. The reduced pressure supplymeans operably connect the cover to a reduced pressure supply sourcethat provides a supply of reduced pressure to the cover, so that thevolume under the cover at the site of the wound is supplied with reducedpressure by the reduced pressure supply source.

In some embodiments, the cover may be approximately cylindrical inshape. In other embodiments, the cover may be approximately cup-shaped.In some embodiments, the sealing means may be comprised of the suctionof the interface member against the body, such suction being produced bythe presence of reduced pressure in the volume under the cover at thesite of the wound. In still other embodiments, the top cup member andthe interface member are each comprised of materials from the groupconsisting of semi-rigid materials, rigid materials, and combinations ofsuch materials. Further, in some embodiments, the interface member isfurther comprised of a membrane portion that is disposed approximatelyadjacent to the body and the flow control means is comprised of at leastone one-way valve operably disposed in the membrane portion. In otherembodiments, the interface member may be further comprised of a membraneportion that is disposed approximately adjacent to the body and thatpermits fluid to flow in only one direction, and the flow control meansis comprised of all or a portion of the membrane. In some embodiments,the interface attachment means may be comprised of an o-ring seal or amagnetic seal. In other embodiments, a portion of the interface membermay be of a size and shape adapted to fit tightly against a portion ofthe top cup member, wherein an operable seal (described in more detailbelow) is created between the interface member and the top cup member.In yet other embodiments, the sealing means may be comprised of anadhesive that is disposed between a portion of the cover and the portionof the body adjacent to said portion of the cover. In still otherembodiments, the sealing means may be comprised of an adhesive tape thatis disposed over a portion of the cover and the portion of the bodyadjacent to said portion of the cover. In other embodiments, the top cupmember is further comprised of a port and flow shutoff means operablyconnected to the port, wherein the flow shutoff means halt or inhibitthe supply of reduced pressure to the cover when the level of exudateunder the cover at the site of the wound reaches a predetermined level.In yet other embodiments, the interface attachment means does notprovide for removal of the top cup member from the interface member.

In some embodiments, the top cup member of the cover may be furthercomprised of a lid member, a cup body member, and lid attachment meansto removably attach the lid member to the cup body member. In some ofthese embodiments, the cover is approximately cylindrical in shape. Inother embodiments, the interface attachment means provides for removableattachment of the top cup member to the interface member, but does notprovide for permanent attachment of the top cup member to the interfacemember. In some embodiments, the interface attachment means may becomprised of an o-ring seal or a magnetic seal. In other embodiments, aportion of the interface member may be of a size and shape adapted tofit tightly against a portion of the top cup member, wherein an operableseal is created between the interface member and the top cup member. Instill other embodiments, the interface attachment means provides forpermanent attachment of the top cup member to the interface member, butdoes not provide for removable attachment of the top cup member to theinterface member. In yet other embodiments, the lid attachment means maybe comprised of an o-ring seal or a magnetic seal. In other embodiments,a portion of the lid member is of a size and shape adapted to fittightly against a portion of the cup body member, wherein an operableseal is created between the lid member and the cup body member.

In other embodiments of the present invention, the cover is comprised ofa lid member, a cup body member, and lid attachment means to removablyattach the lid member to the cup body member. In these embodiments, thecover is sized to be placed over and enclose the wound and adapted tomaintain reduced pressure in the volume under the cover at the site ofthe wound. Also in these embodiments, the sealing means, which aredescribed in more detail below, are used to seal the cup body member ofthe cover to the body so that reduced pressure may be maintained in thevolume under the cover at the site of the wound. Reduced pressure supplymeans operably connect the cover to a reduced pressure supply source,which provides a supply of reduced pressure to the cover so that thevolume under the cover at the site of the wound is supplied with reducedpressure by the reduced pressure supply source. In some embodiments, thelid attachment means may be comprised of an o-ring seal or a magneticseal. In other embodiments, a portion of the lid member is of a size andshape adapted to fit tightly against a portion of the cup body member,wherein an operable seal is created between the lid member and the cupbody member. In some embodiments, a portion of the lid member isapproximately cylindrical in shape and a portion of the cup body memberis approximately cylindrical in shape and said portions have threads andmeans to receive threads, so that when such portions are screwedtogether an operable seal is created between the lid member and the cupbody member.

In some embodiments, an appliance for administering reduced pressuretreatment to a wound on a body is comprised of a treatment device and avacuum system. In various embodiments, the treatment device is alsocomprised of a cover and sealing means, which may have substantially thesame structure, features, characteristics and operation as the cover andsealing means, respectively, described above in connection with otherembodiments of the present invention. In some embodiments, the vacuumsystem is further comprised of a reduced pressure supply source thatprovides a supply of reduced pressure and reduced pressure supply means(which are described in more detail below) to operably connect thetreatment device to the reduced pressure supply source, so that thevolume under the treatment device at the site of the wound is suppliedwith reduced pressure by the reduced pressure supply source. In variousembodiments, the reduced pressure supply means may generally havesubstantially the same structure, features, characteristics, andoperation as the reduced pressure supply means described above inconnection with other embodiments of the invention.

In some embodiments, the reduced pressure supply source is comprised ofa vacuum pump. In some of these embodiments, the reduced pressure supplysource further comprises a control system for the vacuum pump, whereinthe control system may control at least the level of suction produced bythe vacuum pump or the rate of fluid flow produced by the vacuum pump,or any combination of rate of suction and rate of fluid flow of thevacuum pump. In other embodiments, the reduced pressure supply sourcefurther comprises a filter operably positioned between the vacuum pumpand the reduced pressure supply means. In these embodiments, the filterprevents the venting of and contamination of the vacuum pump bymicro-organisms or fluids (or both) aspirated from the wound. In yetother embodiments, the vacuum pump is comprised of a portable vacuumpump. In still other embodiments of the invention, the reduced pressuresupply means is comprised of flexible tubing. In other embodiments, thecover is further comprised of a port and flow shutoff means, wherein theflow shutoff means halts or inhibits the application of reduced pressureto the cover when exudate from the wound reaches a predetermined levelwithin the cover. In yet other embodiments, the reduced pressure underthe cover at the site of the wound is in the range from approximately 20mm of Hg below atmospheric pressure to approximately 125 mm of Hg belowatmospheric pressure. In other embodiments, the reduced pressure isapplied in a cyclic nature, the cyclic nature providing alternating timeperiods of application of reduced pressure and without application ofreduced pressure.

In some embodiments, an appliance for administering reduced pressuretreatment to a wound on a body is comprised of a treatment device and avacuum system. In various embodiments, the treatment device is alsocomprised of a cover and sealing means, which may have substantially thesame structure, features, characteristics and operation as the cover andsealing means, respectively, described above in connection with otherembodiments of the present invention. In various embodiments of theinvention, the vacuum system is comprised of a suction bulb, which may(but not necessarily) provide a source of reduced pressure, and reducedpressure supply means, which are described in more detail below, tooperably connect the cover to the suction bulb, so that the site of thewound in the volume under the cover may be supplied with reducedpressure by the suction bulb. In some embodiments, the suction bulb isfurther comprised of an inlet port and an outlet port, wherein the inletport is operably connected to the reduced pressure supply means, and thevacuum system further comprises an exhaust tubing member operablyconnected to the outlet port. In some of these embodiments, the vacuumsystem further comprises an exhaust control valve operably connected tothe exhaust tubing member. In other embodiments, the vacuum system isfurther comprised of a filter operably connected to the exhaust tubingmember, which prevents the venting of micro-organisms or fluids (orboth) aspirated from the wound. In yet other embodiments, the vacuumsystem is further comprised of a supplemental vacuum system that isoperably connected to the exhaust tubing member. In these embodiments,the supplemental vacuum system may generally have substantially the samestructure, features, characteristics and operation as the vacuum systemdescribed above in connection with other embodiments of the invention.

Another embodiment of the present invention discloses a method oftreating a wound. In one embodiment, the method comprises the followingsteps. First, a cover is positioned on the body over the wound, whereinthe cover may have substantially the same structure, features,characteristics and operation as the embodiments of the cover describedabove in connection with other embodiments of the invention. Second, thecover is operably sealed to the body so that reduced pressure may bemaintained in the volume under the cover at the site of the wound.Third, the cover is operably connected with a vacuum system forproducing reduced pressure in the volume under the cover at the site ofthe wound. Fourth, the reduced pressure is maintained until the woundhas progressed toward a selected stage of healing.

In other embodiments, the vacuum system is comprised of a suction bulband the method further comprises the step of squeezing the suction bulbto reduce its volume and then releasing the suction bulb, so thatreduced pressure is produced in the volume under the cover at the siteof the wound. In other embodiments, the reduced pressure under the coverat the site of the wound is in the range from approximately 20 mm of Hgbelow atmospheric pressure to approximately 125 mm of Hg belowatmospheric pressure. In still other embodiments, the reduced pressureis applied in a cyclic nature, the cyclic nature providing alternatingtime periods of application of reduced pressure and without applicationof reduced pressure. In other embodiments, the cover is furthercomprised of a lid member, a cup body member, and lid attachment meansto removably attach the lid member to the cup body member, and themethod further comprises the steps of halting the application of reducedpressure to the cover, removing the lid member from the cup body member,and attending to the wound. In some of these embodiments, the methodfurther comprises the steps of re-attaching the lid member to the cupbody member after attending to the wound and then reapplying reducedpressure to the volume under the cover in the area of the wound. Instill other embodiments, the top cup member further comprises a port andflow shutoff means operably connected to the port, wherein the flowshutoff means halts or hinders the supply of reduced pressure to thevolume under the cover in the area of the wound when the level ofexudate within the cover reaches a predetermined level. In theseembodiments, the method may further comprise the steps of monitoring thelevel of exudate aspirated from the wound that accumulates within thevolume of the cover and removing the cover from the body when the levelof exudate aspirated from the wound causes the flow shutoff means tohalt or hinder the supply of reduced pressure to the volume under thecover in the area of the wound. It is to be noted that in various otherembodiments the steps described above may be performed in a differentorder than that presented.

Embodiments of the present invention therefore meet the needs discussedabove in the Background section. For example, some embodiments of thepresent invention can eliminate the requirement for a separatecollection device to collect exudate from the wound because the exudateis collected and retained within the volume under the cover. In theseembodiments, the interface member is sealed to the body by the sealingmeans and exudate from the wound flows from the wound through the flowcontrol means in the interface member into the volume of the cover abovethe interface member. The flow control means do not allow the exudate toflow back into the area of the wound under the interface member. Thus,this type of device could reduce the expense involved in wound treatmentby eliminating the need for the collection device. This treatment devicealso removes exudate from the presence of the wound to aid in woundhealing. It is also possible for this type of treatment device to bedisposable. Further, some embodiments allow for physical access to thewound without the need for removing the treatment device from the body.In these embodiments, the lid member may be removed from the cup bodymember of the cover, exposing the area of the wound if an interfacemember is not utilized. This embodiment of the device could enhancepatient comfort because it would not be necessary to remove the sealingmeans to access the wound. In addition, because access is simple andquickly obtained, embodiments of the present invention may also decreasethe cost of wound treatment by reducing the time required of healthcarepractitioners to be involved in wound treatment. Embodiments of thepresent invention should also be relatively inexpensive to produce,while meeting the needs described above. As can be observed from theforegoing discussion, embodiments of the present invention have greatflexibility. In various embodiments, it may be used with or without theinterface member, as well as with or without the removable lid feature.

There has thus been outlined, rather broadly, the more primary featuresof the present invention. There are additional features that are alsoincluded in the various embodiments of the invention that are describedhereinafter and that form the subject matter of the claims appendedhereto. In this respect, it is to be understood that the invention isnot limited in its application to the details of construction and to thearrangements of the components set forth in the following description orillustrated in the following drawings. This invention may be embodied inthe form illustrated in the accompanying drawings, but the drawings areillustrative only and changes may be made in the specific constructionillustrated and described within the scope of the appended claims. Theinvention is capable of other embodiments and of being practiced andcarried out in various ways. Also, it is to be understood that thephraseology and terminology employed herein are for the purpose of thedescription and should not be regarded as limiting.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing summary, as well as the following detailed description ofthe preferred embodiments of the present invention, will be betterunderstood when read in conjunction with the appended drawings, inwhich:

FIG. 1A is a perspective view of an embodiment of an impermeableflexible overlay of a wound treatment appliance, as viewed from the sideof and above the flexible overlay comprising the wound treatmentappliance (as the flexible overlay would be oriented when placed on thebody of a patient);

FIG. 1B is a perspective view of another embodiment of an impermeableflexible overlay of a wound treatment appliance, as viewed from the sideof and above the flexible overlay comprising the wound treatmentappliance (as the flexible overlay would be oriented when placed on thebody of a patient);

FIG. 1C is a perspective view of another embodiment of an impermeableflexible overlay of a wound treatment appliance, as viewed from the sideof and above the flexible overlay comprising the wound treatmentappliance (as the flexible overlay would be oriented when placed on thebody of a patient);

FIG. 1D is a perspective view of another embodiment of an impermeableflexible overlay of a wound treatment appliance, as viewed from the sideof and above the flexible overlay comprising the wound treatmentappliance (as the flexible overlay would be oriented when placed on thebody of a patient);

FIG. 2A is a view of an embodiment of a wound treatment appliance, inwhich an embodiment of an impermeable flexible overlay, shown inperspective view from the side of and above the flexible overlay, coversa wound, and in which an embodiment of a vacuum system, depictedgenerally and shown in schematic elevation view, provides reducedpressure within the area under the flexible overlay;

FIG. 2B is a sectional elevational detailed view of an embodiment of acollection container and the shutoff mechanism portion of the collectionsystem of FIG. 2A;

FIG. 3 is a view of an embodiment of a wound treatment appliance of, inwhich an embodiment of an impermeable flexible overlay, shown incross-sectional elevational view from the side of the flexible overlay,covers a wound and wound packing means, and in which an embodiment of avacuum system, shown in elevational view, provides reduced pressurewithin the area under the flexible overlay;

FIG. 4 is a view of an embodiment of a wound treatment appliance, inwhich an embodiment of an impermeable flexible overlay, shown incross-sectional elevational view from the side of the flexible overlay,covers a wound, and in which an embodiment of a vacuum system, shown inperspective view from the side of and below the vacuum system, providesreduced pressure within the area under the flexible overlay;

FIG. 5 is a view of an embodiment of a wound treatment appliance, inwhich an embodiment of an impermeable flexible overlay, shown inperspective view from the side of and above the flexible overlay, coversa wound, and in which an embodiment of a vacuum system, depictedgenerally and shown in schematic elevation view, provides reducedpressure within the area under the flexible overlay; and

FIG. 6 is a view of another embodiment of a wound treatment appliance,in which an embodiment of an impermeable flexible overlay is shown inpartially broken away perspective view from the side of and above theflexible overlay (as the flexible overlay would be oriented when placedon the body of a patient), and in which an embodiment of a vacuumsystem, depicted generally and shown in schematic elevation view,provides reduced pressure within the area under the flexible overlay.

FIG. 7 is an exploded perspective view of an embodiment of a cover, assuch cover would appear from above the body of a patient while the coveris positioned on the body;

FIG. 8A is an plan view of the interface member of the embodiment of thecover illustrated in FIG. 7, as taken along the lines 8A-8A of FIG. 7;

FIG. 8B is an elevation view of another embodiment of an interfacemember;

FIG. 9 is an enlarged cross-sectional elevation view of one embodimentof the interface attachment means;

FIG. 10 is an enlarged cross-sectional elevation view of anotherembodiment of the interface attachment means;

FIG. 11 is a view of an embodiment of a treatment appliance, in which anembodiment of a treatment device, shown in perspective view, is placedover a wound on a body, and in which an embodiment of a vacuum system,depicted generally and shown in schematic elevation view, providesreduced pressure within the volume under a cover comprising thetreatment device;

FIG. 12 is a view of an embodiment of a treatment appliance, in which anembodiment of a treatment device, shown in perspective view from theside of and above the treatment device, is positioned over a wound on abody, and in which an embodiment of a vacuum system, shown inelevational view, provides reduced pressure within the volume under acover comprising the treatment device.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

In accordance with one embodiment of the present invention, a woundtreatment appliance is provided for treating all or a portion of a woundby applying reduced pressure (i.e., pressure that is below ambientatmospheric pressure) to the portion of the wound to be treated in acontrolled manner for a selected time period in a manner that overcomesthe disadvantages of currently existing apparatus. One embodiment is awound treatment appliance 10 that is comprised of the fluid impermeableflexible overlay 20 illustrated in FIG. 1A and reduced pressure supplymeans, which are described in more detail below. In this embodiment, theflexible overlay 20 has an approximately elongated conical shape, havingan opening 21 with an opening perimeter 22 adjacent to the opening 21(at the base of the elongated conical shape) that is approximatelyelliptical in shape. The flexible overlay 20 illustrated in FIG. 1A isin its natural shape, as it exists prior to being applied to a patientfor treatment of all or a portion of a wound. In other embodiments, theflexible overlay 20 may have other shapes. For example, the flexibleoverlay 20 may be approximately conical in shape, rather than theapproximately elongated conical shape illustrated in FIG. 1A. As anotherexample, as illustrated in FIG. 1B, only the bottom portion 23 a of theflexible overlay 20 a may have an approximately elongated conical shape.In this embodiment, and in the same manner as illustrated in FIG. 1A,the bottom portion 23 a has an opening 21 a with an opening perimeter 22a adjacent to the opening 21 a (at the base of the elongated conicalshape) that is approximately elliptical in shape. In the embodiment ofthe flexible overlay illustrated in FIG. 1B, the top portion 24 a isflatter than the comparable portion of the flexible overlay 20 in theembodiment illustrated in FIG. 1A. In other embodiments, the top portion24 a of the flexible overlay 20 a may have almost any shape that isadaptable to a bottom portion 23 a having an approximately elongatedconical shape. In addition, in yet other embodiments of the invention,the bottom portion 23 a of the flexible overlay 20 a may be in theapproximate shape of a cone, rather than the elongated conical shapeillustrated in FIG. 1B. In yet another embodiment, as illustrated inFIG. 1C, the flexible overlay 20 b is comprised of six cover portions 23b, 23 b′, where the cover portions 23 b are viewable in FIG. 1C and thecover portions 23 b′ are illustrated by phantom lines. In thisembodiment, each of such cover portions 23 b, 23 b′ is approximatelytriangular in shape, and one point of each of the at least three coverportions 23 b, 23 b′ is joined to form an apex 24 b of the impermeableflexible overlay 20 b. One side of each cover portion 23 b, 23 b′adjacent to the apex 24 b is joined to an adjacent side of another ofsuch cover portions 23 b, 23 b′ so that the bases 22 b, 22 b′ of thecover portions 23 b, 23 b′, respectively, form an opening 21 b sized tobe placed over and enclose the area of the wound to be treated. In otherembodiments, the flexible overlay 20 b may have a different number ofcover portions 23 b, 23 b′. Preferably, in these embodiments, there areat least three cover portions 23 b, 23 b′. In addition, in yet otherembodiments, the flexible overlay 20 b may have cover portions 23 b, 23b′ having a different shape, such as trapezoidal or parabolic. Anotherembodiment of the present invention is illustrated in FIG. 1D. In thisembodiment, the overlay 20 c is approximately cup-shaped with anapproximately circular opening 21 c, which has an opening perimeter 22 cadjacent to the opening 21 c. The overlay 20 c of this embodiment alsohas a plurality of channels 29 c disposed in the surface thereof assuction assist means, which are described in more detail below. In stillother embodiments, the flexible overlay 20, 20 a, 20 b, 20 c may be ofalmost any shape that may be adaptable for treating all or a portion ofa wound, as long as the flexible overlay 20, 20 a, 20 b, 20 c isflexible, as described in more detail below, and the interior surface ofthe flexible overlay 20, 20 a, 20 b, 20 c is adapted to make anapproximately hermetic seal with the body of the patient at the site ofthe wound, as described in more detail below. For example, and asclarification, the flexible overlay 20, 20 a, 20 b, 20 c or portionsthereof may have an approximately tetrahedral, hexahedral, polyhedral,spherical, spheroidal, arcuate, or other shape or combination of allsuch shapes. Referring again to FIG. 1A as an example, in someembodiments, the interior surface of the flexible overlay 20 is adaptedto make an approximately hermetic seal with the body of the patient atthe site of the wound by having a surface area larger than the surfacearea of the portion of the body of the patient covered by the flexibleoverlay 20, as described in more detail below.

The preferred shape and size of the flexible overlay 20, 20 a, 20 b, 20c is dependent upon the size of the portion of the wound to be treated,the shape and contour of the portion of the body that is to be coveredby the flexible overlay 20, 20 a, 20 b, 20 c at the site of the wound,the magnitude of the reduced pressure to be maintained under theflexible overlay 20, 20 a, 20 b, 20 c. More preferred, as illustrated inFIG. 1B, the flexible overlay 20 a has an approximately elongatedconically shaped bottom portion 23 a. Most preferred, as illustrated inFIG. 1A, the flexible overlay 20 is shaped approximately as an elongatedcone. The preferred thickness of the portion 25, 25 a, 25 b, 20 c of theflexible overlay 20, 20 a, 20 b, 20 c adjacent to the open end 21, 21 a,21 b, 20 c of the flexible overlay 20, 20 a, 20 b, 20 c is dependentupon the size and shape of the flexible overlay 20, 20 a, 20 b, 20 c,the shape and contour of the portion of the body that is to be coveredby the flexible overlay 20, 20 a, 20 b, 20 c at the site of the wound,the magnitude of the reduced pressure to be maintained under theflexible overlay 20, 20 a, 20 b, 20 c, and other factors, such as thedepth of the wound and the amount of the desired collapse of theflexible overlay 20, 20 a, 20 b, 20 c. For example, in the embodimentillustrated in FIG. 1A, for a flexible overlay 20 constructed ofsilicone and having an approximately elongated conical shape with anopening 21 having a major diameter of approximately 7 inches and a minordiameter of approximately 4 inches, the preferred thickness of theportion 25 of the flexible overlay 20 adjacent to the open end 21 of theflexible overlay 20 is in the range from 1/32 inches to 3/32 inches.More preferred in this embodiment, the thickness of the portion 25 ofthe flexible overlay 20 adjacent to the open end 21 of the flexibleoverlay 20 is approximately 1/16 inches. It is to be noted that in otherembodiments the thickness of the flexible overlay 20, including theportion 25 of the flexible overlay 20 adjacent to the open end 21 of theflexible overlay 20, may vary from location to location on the flexibleoverlay 20.

In the embodiment of the flexible overlay 20 illustrated in FIG. 1A, theflexible overlay 20 has a series of raised beads 26 on the outsidesurface of the flexible overlay 20. In this embodiment, the raised beads26 are generally parallel to the perimeter 22 of the opening 21 of theflexible overlay 20. The same is also true of the raised bead 26 b ofthe flexible overlay 20 b of the embodiment illustrated in FIG. 1C. Inother embodiments, such as that illustrated in FIG. 1B, the raised beads26 a may have a different orientation. In still other embodiments, theraised beads 26, 26 a, 26 b may be in almost any orientation desired bythe user of the wound treatment appliance 10, 10 a, 10 b. In variousembodiments, as illustrated in FIG. 1A, the raised beads 26 may providea guide for the user administering the reduced pressure treatment to cutaway a portion of the flexible overlay 20, so that the perimeter 22 ofthe opening 21 of the flexible overlay 20 is smaller than it wasoriginally. For example, by cutting along the parallel raised beads 26of the flexible overlay 20 of FIG. 1A, the size of the opening 21 of theflexible overlay 20 can be made smaller while the shape of the perimeter22 remains approximately the same. It is to noted, however, that invarious embodiments of the invention, as described in more detail below,the flexible overlay 20 may be cut into different shapes in order toadapt the flexible overlay 20 for use with different shapes and contoursof the surface of the body at the site of the wound.

In other embodiments of the present invention, as illustrated in FIG.1D, the flexible overlay 20 c may be further comprised of suction assistmeans to assist in the application of reduced pressure to the portion ofthe wound to be treated, as well as removal of exudate from the wound.For example, in the illustrated embodiment, the overlay 20 c has aplurality of channels 29 c disposed in the surface thereof. The channels29 c may generally provide a conduit for reduced pressure to reach thevarious portions of the wound to be treated. In addition, exudateaspirated from the various portions of the wound to be treated may flowalong the channels 29 c to the reduced pressure supply means (notillustrated), where the exudate may be removed from the flexible overlay20 c by means of the reduced pressure supply means cooperating with thereduced pressure supply source, as described in more detail below. Insome of these embodiments, the channels 29 c may be operably connectedto the reduced pressure supply means through a port 27 c, as describedin more detail below. In the illustrated embodiment, there are threecontinuous channels 29 c recessed into the surface of the overlay 20 c,which are joined together near the apex of the flexible overlay 20 c atthe port 27 c. In other embodiments, there may be more or fewer channels29 c. For example, in other embodiments, there may be fewer channels 29c and the channels 29 c may be of the same size or of a different size.In yet other embodiments, there may be many channels 29 c, in which casethe channels 29 c may generally be of a smaller size. In addition, thechannels 29 c may be disposed in other positions relative to theflexible overlay 20 c. For example, the channels 29 c may be located atdifferent locations on the flexible overlay 20 c and may have adifferent orientation, such as being curved in a “corkscrew” pattern orcrossed in a “checkerboard” pattern, rather than being oriented asillustrated in FIG. 1D. In still other embodiments, the channels 29 c,as suction assist means, may have a different structure and form. Forexample, the channels 29 c may be in the form of tubes positioned withinthe volume of the flexible overlay 20 c, wherein the tubes have one ormore perforations so that the channels 29 c are in fluid communicationwith the volume under the flexible overlay 20 c in the area of the woundto be treated. As another example, the channels 29 c may have stiffeningmembers, such as raised beads (“ribs”) of material, so that the channels29 c have a greater stiffness than the remaining portions of theflexible overlay 20 c. In other embodiments, the channels 29 c, assuction assist means, may be in the form of portions that are raisedabove the surface of the flexible overlay 20 c. Such raised portions mayappear as “dimples” when viewed from above the flexible overlay 20 c.The channels 29 c, as suction assist means, may also be of almost anysize, shape and pattern to accomplish their intended purpose. Thepreferred size, shape and pattern are dependent upon the size and shapeof the flexible overlay 20 c, the type of wound to be treated, the levelof reduced pressure to be used in the treatment, the amount of exudateanticipated, the type of reduced pressure supply means utilized, and theindividual preference of the user of the appliance 10 c. Where utilized,channels 29 c may be molded or cut into the surface of the flexibleoverlay 20 c or, if in the shape of tubes, may be molded as a part ofthe surface of the flexible overlay 20 c or may be welded or fused tothe surface of the flexible overlay 20 c. It is to be noted that thevarious embodiments of the flexible overlays 20, 20 a, 20 b illustratedand described above in connection with FIG. 1A, FIG. 1B, and FIG. 1C,respectively, may each also comprise suction assist means, and thereforemay also comprise any of the various embodiments of the channels 29 cillustrated and described above in connection with FIG. 1D.

In various embodiments, the flexible overlay 20, 20 a, 20 b, 20 c may becomprised of almost any medical grade flexible material that iscurrently known in the art or that may be developed in the art in thefuture, as long as such material is fluid-impermeable, suitable forpurposes of wound treatment (e.g., can be sterilized and does not absorbsignificant amounts of wound exudate), and is capable of forming anapproximately hermetic seal with the surface of the body at the site ofthe wound, as described in more detail below. For example, the flexibleoverlay 20, 20 a, 20 b, 20 c may be comprised of rubber (includingneoprene), and flexible polymer materials, such as silicone, siliconeblends, silicone substitutes, polyester, vinyl, polyimide, polyethylenenapthalate, polycarbonates, polyester-polycarbonate blends, or a similarpolymer, or combinations of all such materials. Preferably, the flexibleoverlay 20, 20 a, 20 b, 20 c is comprised of silicone. Although theraised beads 26, 26 a, 26 b may be constructed of a material differentfrom the material comprising the remainder of the flexible overlay 20,20 a, 20 b in various embodiments of the invention, the raised beads 26,26 a, 26 b are preferably constructed from the same material comprisingthe remainder of the flexible overlay 20, 20 a, 20 b. In otherembodiments, the raised beads 26, 26 a, 26 b may be placed on theflexible overlay 20, 20 a, 20 b by means of a mark, such as indelibleink, on the surface of the flexible overlay 20, 20 a, 20 b. In someembodiments, the channels 29 c (and all other suction assist means) maybe constructed of a material different from the material comprising theremainder of the flexible overlay 20 c. For example, one or more of thechannels 29 c may be constructed of a slightly more rigid material thanthe remainder of the flexible overlay 20 c so that such channel 29 c orchannels 29 c better retain their shape. In other embodiments, thechannels 29 c may be constructed of the same material comprising theremainder of the flexible overlay 20 c, but the channels 29 c may have adifferent thickness than the remainder of the flexible overlay 29 c. Forexample, one or more of the channels 29 c may be slightly thicker thanthe remainder of the flexible overlay 20 c so that such channel 29 c orchannels 29 c better retain their shape. In still other embodiments, thechannels 29 c may be constructed of the same material comprising, andhave the same thickness as, the remainder of the flexible overlay 20 c.Preferably, the channels 29 c are constructed of the same material as,but have a slightly greater thickness than, the remaining portions ofthe flexible overlay 20 c. It is to be noted that in various embodimentsof the invention, the flexible overlay 20, 20 a, 20 b, 20 c may beconstructed in whole or in part of gas-permeable materials, allowinglimited amounts of oxygen to penetrate the flexible overlay 20, 20 a, 20b, 20 c so that the area of the wound under the flexible overlay 20, 20a, 20 b, 20 c can “breathe.” It is also to be noted that all portions ofthe flexible overlay 20, 20 a, 20 b, 20 c are preferably constructed ofone type of polymer material, such as silicone. The flexible overlay 20,20 a, 20 b, 20 c may be constructed using any suitable means currentlyknown in the art or that may be developed in the art in the future. Forexample, a flexible overlay 20, 20 a, 20 b, 20 c constructed of siliconemay be manufactured by means of injection molding. As another example,where the channels 29 c are constructed of a different material from theremainder of the flexible overlay 20 c, the channels 29 c may be weldedor fused to the remaining portions of the flexible overlay 20 c.

In the embodiments of the flexible overlay 20, 20 a, 20 b, 20 cillustrated in FIG. 1A, FIG. 1B, FIG. 1C, and FIG. 1D, respectively,each of the flexible overlays 20, 20 a, 20 b, 20 c further comprises aport 27, 27 a, 27 b, 27 c adapted to receive a reduced pressure supplymeans to supply reduced pressure to the area of the wound under theflexible overlay 20, 20 a, 20 b, 20 c. Although the port 27 ispositioned at approximately the apex of the elongated cone-shapedflexible overlay 20 in the embodiment illustrated in FIG. 1A, and theport 27 b is positioned at approximately the apex 24 b of thetriangular-shaped cover portions 23 b, 23 b′ in the embodimentillustrated in FIG. 1C, which is the preferred location, the port may belocated at another location on the flexible overlay in otherembodiments. In such embodiments, and referring to FIG. 1B as anexample, the port 27 a (and alternate port 27 a′) may be located atalmost any location on the surface of the flexible overlay 20 a as longas the port 27 a, 27 a′ does not adversely affect the ability of theflexible overlay 20 a to make an approximately hermetic seal with thesurface of the body at the wound site, as described in more detailbelow. For example, the port 27 a, 27 a′ may not be located too close tothe perimeter 22 a of the opening 21 a of the flexible overlay 20 abecause the approximately hermetic seal with the surface of the body istypically formed at that location. In the embodiment of the flexibleoverlay 20 a illustrated in FIG. 1B, the alternate port 27 a′ maypreferably be located at any location on the top portion 24 a of theflexible overlay 20 a, and more preferably, the port 27 a is located atthe center of the top portion 24 a of the flexible overlay 20 a.Referring again to FIG. 1A as an example, although the port 27 may beconstructed of a material different from the material comprising theremainder of the flexible overlay 20 in various embodiments of theinvention, the port 27 is preferably constructed from the same materialcomprising the remainder of the flexible overlay 20. In the embodimentsof the flexible overlay 20, 20 a, 20 b illustrated in FIG. 1A, FIG. 1B,and FIG. 1C, respectively, the ports 27, 27 a, 27 b are generallycylindrical in shape and are further comprised of an approximatelycylindrical duct 28, 28 a, 28 b, respectively, that extends from the topof each of the ports 27, 27 a, 27 b, respectively, to the bottom of theports 27, 27 a, 27 b, respectively. The ports 27, 27 a, 27 b of theseembodiments are thus able to receive a vacuum system or reduced pressuresupply means, which are described in more detail below, adapted to beconnected to this shape of port 27, 27 a, 27 b, respectively, andchannel 28, 28 a, 28 b, respectively. In other embodiments of theinvention, the ports 27, 27 a, 27 b, 27 c or the port ducts 28, 28 a, 28b, respectively, or both may have different shapes and configurations asmay be desired to adapt and connect the ports 27, 27 a, 27 b,respectively, and the port ducts 28, 28 a, 28 b, respectively, to thevacuum system or reduced pressure supply means, which are described inmore detail below. For example, the port 27 c of the flexible overlay 20c illustrated in FIG. 1D is formed as a single piece with the remainderof the flexible overlay 20 c. In this example, the port 27 c has acylindrical duct 28 c that extends through the port 27 c and generallyfollows the contours of the channels 29 c at its lower end.

Another embodiment of the present invention is the wound treatmentappliance 110 illustrated in FIG. 2A. In this embodiment, the woundtreatment appliance 110 is comprised of a wound treatment device 115 anda vacuum system, generally designated 150, that is operably connectedto, and provides a supply of reduced pressure to, the wound treatmentdevice 115. Also in this embodiment, the wound treatment device 115 iscomprised of a flexible overlay 120. In addition, in this embodiment,the vacuum system 150 is further comprised of a reduced pressure supplysource, generally designated 130, which is illustrated schematically anddescribed in more detail below, and reduced pressure supply means,generally designated 140, which are illustrated schematically anddescribed in more detail below. Also in this embodiment, the reducedpressure supply means 140 are used to connect the reduced pressuresupply source 130 to the flexible overlay 120 in a manner so thatreduced pressure is supplied to the volume under the flexible overlay120 in the area of the wound 160, as described in more detail below. Inthe embodiment illustrated in FIG. 2A, the flexible overlay 120 hassubstantially the same structure, features, characteristics andoperation as the flexible overlay 20 described above and illustrated inconnection with FIG. 1A. It is to be noted, however, that in otherembodiments, the flexible overlay 120 may have substantially the samestructure, features and characteristics as any embodiment of all of theflexible overlays 20, 20 a, 20 b, 20 c of the embodiments describedabove and illustrated in connection with FIG. 1A, FIG. 1B, FIG. 1C, andFIG. 1D. FIG. 2A also illustrates an example of how the embodiment ofthe flexible overlay 20 illustrated in FIG. 1A may be used to providereduced pressure treatment for a wound 160 on the body 170 of a patient.In this example, the flexible overlay 120 is placed over and enclosesthe entire wound 160, as described in more detail below. In otherembodiments, the flexible overlay 120 need not enclose the entire wound160.

In the embodiment illustrated in FIG. 2A, the reduced pressure supplysource 130 of the vacuum system 150, which produces a source of reducedpressure or suction that is supplied to the flexible overlay 120, iscomprised of a vacuum pump 131, a control device 132, and a filter 133.Although the preferred means of producing the reduced pressure orsuction is a vacuum pump 131 in this embodiment, in other embodiments ofthe invention other means may be used, such as an outlet port of acentralized hospital vacuum system. In the illustrated embodiment,predetermined amounts of suction or reduced pressure are produced by thevacuum pump 131. The vacuum pump 131 is preferably controlled by acontrol device 132, such as a switch or a timer that may be set toprovide cyclic on/off operation of the vacuum pump 131 according touser-selected intervals. Alternatively, the vacuum pump 131 may beoperated continuously without the use of a cyclical timer. In addition,in some embodiments the control device 132 may provide for separatecontrol of the level of reduced pressure applied to the wound 160 andthe flow rate of fluid aspirated from the wound 160. In theseembodiments, relatively low levels of reduced pressure may be maintainedin the area of the wound 160 under the wound treatment device 115, whilestill providing for the removal of a relatively large volume of exudatefrom the wound 160. A filter 133, such as a micropore filter, ispreferably attached to the inlet of the vacuum pump 131 to preventpotentially pathogenic microbes or aerosols from contaminating, and thenbeing vented to atmosphere by, the vacuum pump 131. In otherembodiments, the filter 133 may also be a hydrophobic filter thatprevents any exudate from the wound from contaminating, and then beingvented to atmosphere by, the vacuum pump 131. It is to be noted that inother embodiments of the invention, the reduced pressure supply source130 may not have a filter 133 or a control 132 or any combination of thesame.

In the embodiment illustrated in FIG. 2A, the reduced pressure supplymeans 140 of the vacuum system 150, which are used to connect thereduced pressure supply source 130 to the flexible overlay 120 so thatreduced pressure is supplied to the volume under the flexible overlay120 in the area of the wound 160 is comprised of at least one tubingmember 141. In this embodiment, the at least one tubing member 141 issufficiently flexible to permit movement of the at least one tubingmember 141, but is sufficiently rigid to resist constriction whenreduced pressure is supplied to the flexible overlay 120 or when thelocation of the wound 160 is such that the patient must sit or lie uponthe at least one tubing member 141 or upon the wound treatment device115. In the embodiment illustrated in FIG. 2A, the at least one tubingmember 141 is connected to the flexible overlay 120 by inserting one endof the at least one tubing member 141 into the opening 128 of the port127 of the flexible overlay 120. In this embodiment, the at least onetubing member is held in place in the opening 128 by means of anadhesive. It is to be noted that in other embodiments of the invention,the at least one tubing member 141 may be connected to the port 127 ofthe flexible overlay 120 using any suitable means currently known in theart or developed in the art in the future. Examples include variabledescending diameter adapters (commonly referred to as “Christmas tree”adapters), luer lock fittings and adapters, clamps, and combinations ofsuch means. Alternatively, the port 127 and the at least one tubingmember 141 may be fabricated as a single piece, as is the case with theport 27 c of the flexible overlay 20 c, as illustrated and describedabove in connection with FIG. 1D. Similar means may be used to connectthe other end of the at least one tubing member 141 to the vacuum pump131 or other reduced pressure supply source 130 providing the reducedpressure.

In the embodiment illustrated in FIG. 2A, the reduced pressure supplymeans 140 further comprises a fluid collection system, generallydesignated 142, that is interconnected between the suction pump 131 andthe flexible overlay 120 to remove and collect any exudate that may beaspirated from the wound 160 and collected by the flexible overlay 120.The flexible overlay 120 functions to actively draw fluid or exudatefrom the wound 160. Collection of exudate in a fluid collection system142 intermediate the pump 131 and the flexible overlay 120 is desirableto prevent clogging of the pump 131. The fluid collection system 142 iscomprised of a fluid-impermeable collection container 143 and a shutoffmechanism 144, which are described in more detail below in connectionwith FIG. 2B. The container 143 may be of any size and shape capable ofintercepting and retaining a predetermined amount of exudate. Manyexamples of such containers are available in the relevant art. Referringto FIG. 2B, which is an enlarged elevational cross-sectional view of thepreferred embodiment of the container 143, the container 143 includes afirst port 143 a at the top opening of the container 143 for sealedconnection to tubing member 141 a, where the other end of the tubingmember 141 a is connected to the flexible overlay 120. The first port143 a enables suction to be applied to the flexible overlay 120 throughthe tubing 141 a and also enables exudate from the portion of the wound160 covered by the flexible overlay 120 to be drained into the container143. The container 143 provides a means for containing and temporarilystoring the collected exudate. A second port 143 b is also provided onthe top of the container 143 to enable the application of suction fromthe vacuum pump 131. The second port 143 b of the collection system 142is connected to the vacuum pump 131 by tubing member 141 b. Thecollection system 142 is sealed generally gas-tight to enable thesuction pump 131 to supply suction to the flexible overlay 120 throughthe collection system 142.

The embodiment of the collection system 142 illustrated in FIG. 2B alsoincludes a shutoff mechanism for halting or inhibiting the supply of thereduced pressure to the flexible overlay 120 in the event that theexudate aspirated from the wound 160 exceeds a predetermined quantity.Interrupting the application of suction to the flexible overlay 120 isdesirable to prevent exsanguination in the unlikely event a blood vesselruptures under the flexible overlay 120 during treatment. If, forexample, a blood vessel ruptures in the vicinity of the wound 160, ashut-off mechanism would be useful to prevent the vacuum system 150 fromaspirating any significant quantity of blood from the patient. In oneembodiment of the shutoff mechanism 144, as illustrated in FIG. 2B, theshutoff mechanism 144 is a float valve assembly in the form of a ball144 a which is held and suspended within a cage 144 b positioned below avalve seat 144 c disposed within the opening at the top of the containerbelow the second port 143 b that will float upon the exudate and will belifted against the valve seat 144 c as the container 143 fills withexudate. When the ball 144 a is firmly seated against the valve seat 144c, the float valve blocks the second port 143 b and thereby shuts offthe source of suction from the vacuum system 150. In other embodimentsof the container 143, other types of mechanisms may also be employed todetect the liquid level within the container 143 in order to arrestoperation of the vacuum system 50. In addition, in various embodiments,the shutoff mechanism 144 may be comprised of any means that enables thevacuum system 150 to halt the supply of reduced pressure to the flexibleoverlay 120 at any time that the volume of exudate from the wound 160exceeds a predetermined amount. Such means may include mechanicalswitches, electrical switches operably connected to the vacuum systemcontroller 132, optical, thermal, or weight sensors operably connectedto the vacuum system controller 132, and any other means that arecurrently known in the relevant art or that may be developed in the artin the future.

In some embodiments, the wound treatment appliance 110 further comprisestissue protection means 175 to protect and strengthen the body tissue171 that is adjacent to the flexible overlay 120 at the wound site 161.The tissue protection means 175 protects the tissue 171 by preventingabrasion and maceration of the tissue. Preferably, the tissue protectionmeans 175 is a hydrocolloid material, such as COLOPAST Hydrocolloid2655, anhydrous lanoline, or any combination of such hydrocolloidmaterials. More preferably, the tissue protection means 175 is COLOPASTHydrocolloid 2655. The tissue protection means 175 may be applied to thebody tissue 171 to be protected, or it may be applied to the surface ofthe flexible overlay 120 that is to be in contact with the body tissue171, or both, prior to placing the flexible overlay 120 on the surfaceof the body 170 at the wound site 161. It is to be noted thatapplication of the tissue protection means 175 to the body tissue 171that is adjacent to the flexible overlay 120 at the wound site 161 mayonly entail application of the tissue protection means 175 to theportion of the body tissue 171 adjacent to the flexible overlay 120 thatrequires such protection.

FIG. 2A also illustrates an example of how the embodiment of theflexible overlay 20 illustrated in FIG. 1A (which is flexible overlay120 in FIG. 2A) may be used to provide reduced pressure treatment for awound 160 on the body 170 of a patient. In this example, the flexibleoverlay 120 is removed from an aseptic package in which it is stored.The flexible overlay 120 is then placed over and encloses the portion ofthe wound 160 to be treated, which is the entire wound 160 in thisexample. The flexible overlay 120 is also connected to the vacuum system150 by means of the port 127 on the flexible overlay 120 either before,after or during the placement of the flexible overlay 120 over the wound160. Where it is deemed necessary by the user of the wound treatmentappliance 110, tissue protection means 175, as described above, may beplaced on a portion of the flexible overlay 120, on the body tissue 171to be protected, or both, prior to placing the flexible overlay 120 overthe wound 160. In the example illustrated in FIG. 2A, the interiorsurface portions 129 of the flexible overlay 120 positioned around andadjacent to the perimeter 122 of the opening 121 of the flexible overlay120 are at (or can be deformed to be at) a relatively acute anglerelative to the surrounding surface of the body 170. Such deformationmay be caused by the user of the wound treatment appliance 110 exertingmild pressure on the portions 129 of the flexible overlay 120 positionedaround and adjacent to the perimeter 122 of the opening 121 of theflexible overlay 120 so that they are in contact with the surface of thebody 170 surrounding the wound 160. Reduced pressure is then supplied tothe flexible overlay 120 by the vacuum system 150. When reduced pressureis applied to the volume under the flexible overlay 120 in the area ofthe wound 160, the flexible overlay 120 is drawn downward by the reducedpressure, collapsing the flexible overlay 120 in the approximatedirection of the wound 160. As the flexible overlay 120 collapses, theportions 129 of the flexible overlay 120 adjacent to the perimeter 122of the opening 121 of the flexible overlay 120 are drawn tightly againstthe surface of the body 170 surrounding the wound 160, thus forming anapproximately hermetic seal between the portions 129 of the flexibleoverlay 120 adjacent to the perimeter 122 of the opening 121 of theflexible overlay 120 and the portion of the body 170 adjacent to suchportions 129. References to an “approximately hermetic seal” hereinrefer generally to a seal that may be made gas-tight and liquid-tightfor purposes of the reduced pressure treatment of the wound 160. It isto be noted that this seal need not be entirely gas-tight andliquid-tight. For example, the approximately hermetic seal may allow fora relatively small degree of leakage, so that outside air may enter thevolume under the flexible overlay 120 in the area of the wound 160, aslong as the degree of leakage is small enough so that the vacuum system150 can maintain the desired degree of reduced pressure in the volumeunder the flexible overlay 120 in the area of the wound 160. As anotherexample, the approximately hermetic seal formed by the collapsingflexible overlay 120 may not be solely capable of maintaining thereduced pressure in the volume under the flexible overlay 120 in thearea of the wound 160. This may be the case if the shape of the body 170at the site of the wound 160 does not allow for such a seal. In otherinstances, as may be the case with the flexible overlay 20 c illustratedand described above in connection with FIG. 1D, the perimeter 22 cadjacent to the opening 21 c may not have a relatively acute anglerelative to the surrounding tissue, so that additional means is requiredto make an approximately hermetic seal. In these cases, it may benecessary to provide supplemental sealing means, which are used toprovide a seal between the portions of the flexible overlay 120 and thebody 170 where the approximately hermetic seal is not adequate to permitreduced pressure to be maintained in the volume under the flexibleoverlay 120 in the area of the wound 160. For example, in theillustrated embodiment, the supplemental sealing means 176 may be anadhesive applied to a portion of the impermeable overlay 120 or aportion of the body 170 in a manner similar to the application of thetissue protection means 175 described above. In other embodiments, thesupplemental sealing means 176 may be comprised of almost any suitablemeans to provide an adequate seal. For example, the supplemental sealingmeans 176 may be comprised of an adhesive, an adhesive tape, a stretchfabric that covers the wound treatment device 115 and is wrapped arounda portion of the body 170 of the patient in the area of the wound 160,lanoline, or any combination of such means. It is also to be noted thatin this embodiment at least one fold 129 a forms in the surface of theflexible overlay 120 when it collapses, so that exudate aspirated by thewound 160 flows along the at least one fold 129 a to the port 127, wherethe exudate is removed from the flexible overlay 120 by means of thereduced pressure supply means 140 cooperating with the reduced pressuresupply source 130. Thus, in some embodiments, the impermeable overlay120 is constructed of a material, and has a size, shape and thickness,that permits the flexible overlay 120 to collapse in the direction ofthe wound 160 and form an approximately hermetic seal with the body 170when reduced pressure is applied to the volume under the flexibleoverlay 120 in the area of the wound 160, while still being rigid enoughto support the approximately hermetic seal with the body 170 and tosupport the at least one fold 129 a. In embodiments of the overlay 120comprising suction assist means, such as the channels 29 c of theflexible overlay 20 c illustrated and described above in connection withFIG. 1D, exudate from the wound 160 may also flow along such channels tothe port 127. It is also to be noted that the volume under the flexibleoverlay 120 in the area of the wound 160 may be minimal while theflexible overlay 120 is in its collapsed state over the wound 160. Insome embodiments, the reduced pressure maintained in the volume underthe flexible overlay 120 in the area of the wound 160 is in the rangefrom approximately 20 mm of Hg below atmospheric pressure toapproximately 125 mm of Hg below atmospheric pressure. In yet otherembodiments, the reduced pressure is applied to the flexible overlay 120in a cyclic nature, the cyclic nature providing alternating time periodsof application of reduced pressure and non-application of reducedpressure. In all of these embodiments, the reduced pressure ismaintained in the volume under the flexible overlay 120 in the area ofthe wound 160 until the wound 160 has progressed toward a selected stageof healing.

Another embodiment of the invention is the wound treatment appliance 210illustrated in FIG. 3. In this embodiment, the wound treatment appliance210 is comprised of a wound treatment device 215 and a vacuum system,generally designated 250, that is operably connected to, and provides asupply of reduced pressure to, the wound treatment device 215. Inaddition, in this embodiment, the vacuum system 250 is further comprisedof a reduced pressure supply source, generally designated 280, which isdescribed in more detail below, and reduced pressure supply means,generally designated 240, which are described in more detail below. Alsoin this embodiment, the wound treatment device 215 is further comprisedof a flexible overlay 220, wound packing means 278, and a suction drain245. In the embodiment illustrated in FIG. 3, the flexible overlay 220has substantially the same structure, features, characteristics andoperation as the flexible overlay 20 described above and illustrated inconnection with FIG. 1A. It is to be noted, however, that in otherembodiments, the flexible overlay 220 may have substantially the samestructure, features, characteristics, and operation as any embodiment ofall of the flexible overlays 20, 20 a, 20 b, 20 c described above andillustrated in connection with FIG. 1A, FIG. 1B, FIG. 1C, and FIG. 1D,respectively. It is also to be noted that in other embodiments the woundtreatment device 220 may be comprised of almost any type of flexible,semi-rigid, or rigid wound covering apparatus currently known in therelevant art or that may be developed in the relevant art in the futurethat has a port and is designed to cover and enclose a wound andmaintain reduced pressure in the area of the wound under the woundcovering apparatus. For example, the overlay 220 may generally havesubstantially the same structure, features and characteristics as theembodiments of the rigid, semi-rigid or flexible wound covers describedin U.S. patent application Ser. No. 10/652,100, which was filed by thepresent inventor with the U.S. Patent and Trademark Office on Aug. 28,2003, and U.S. patent application Ser. No. 11/026,733, now U.S. Pat. No.7,128,735, entitled “Improved Reduced Pressure Wound TreatmentAppliance,” which was filed by the present inventor with the U.S. Patentand Trademark Office on Dec. 30, 2004, the disclosures of which areincorporated herein by reference. In these embodiments, the overlay 220may be sealed to the body in the area of the wound using any meansdisclosed in such applications or using the supplemental sealing means176 described above and illustrated in connection with FIG. 2A. In theembodiment illustrated in FIG. 3, the flexible overlay 220 is placedover and encloses the entire wound 260 and is illustrated in a state ofpartial collapse, with the portion 229 of the flexible overlay 220adjacent to the opening 221 in the perimeter 222 of the flexible overlay220 forming an approximately hermetic seal with the adjacent portions271 of the body 270. It is to be noted that in various embodiments, thewound treatment appliance 210 may also be comprised of tissue protectionmeans 275, which may be substantially the same as the tissue protectionmeans 175 described above and illustrated in connection with FIG. 2A.

In the embodiment of the invention illustrated in FIG. 3, the woundtreatment device 215 is further comprised of wound packing means 278,which is placed in the area of the wound 260 under the flexible overlay220. In this embodiment, the flexible overlay 220 is placed over thearea of the wound 260 to be treated and the wound packing means 278 whenthe flexible overlay 220 is positioned on the surface of the body 270 atthe site of the wound 260. In some embodiments, the wound packing means278 may be placed within the wound 260 to prevent overgrowth of thetissue in the area of the wound 260. For example, and preferably inthese cases, the wound packing means 278 may comprised of absorbentdressings, antiseptic dressings, nonadherent dressings, water dressings,or combinations of such dressings. More preferably, the wound packingmeans 278 may be comprised of gauze or cotton or any combination ofgauze and cotton. In still other embodiments, the wound packing means278 may be comprised of an absorbable matrix adapted to encourage growthof the tissue in the area of the wound 260 into the matrix. In theseembodiments, the absorbable matrix (as wound packing means 278) isconstructed of an absorbable material that is absorbed into theepithelial and subcutaneous tissue in the wound 260 as the wound 260heals. The matrix (as wound packing means 278) may vary in thickness andrigidity, and it may be desirable to use a spongy absorbable materialfor the patient's comfort if the patient must lie upon the woundtreatment device 215 during treatment. The matrix (as wound packingmeans 278) may also be perforated and constructed in a sponge-type orfoam-type structure to enhance gas flow and to reduce the weight of thematrix. Because of the absorbable nature of the absorbable matrix (aswound packing means 278), the matrix should require less frequentchanging than other dressing types during the treatment process. Inother circumstances, the matrix (as wound packing means 278) may notneed to be changed at all during the treatment process. In someembodiments, the absorbable matrix (as wound packing means 278) may becomprised of collagens or other absorbable materials or combinations ofall such materials. U.S. patent application Ser. No. 10/652,100, whichwas filed by the present inventor with the U.S. Patent and TrademarkOffice on Aug. 28, 2003 and published as U.S. Publication No.2004/0073151 A1, and is hereby incorporated by reference, also disclosesvarious embodiments of an absorbable matrix that may be utilized withvarious embodiments of the present invention. It is to be noted,however, that wound packing means 278 may not be utilized in otherembodiments of the invention.

In the embodiment illustrated in FIG. 3, the wound treatment device 215is also comprised of a suction drain 245 and suction drain connectionmeans, which are described in more detail below, to operably connect thereduced pressure supply means 240 to the suction drain 245 so that thesuction drain 245 is in fluid communication with the reduced pressuresupply means 240 and reduced pressure is supplied to the volume underthe flexible overlay 220 in the area of the wound 260 by means of thesuction drain 245. In this embodiment, the suction drain 245 is furthercomprised of a bottom drain portion 245 a extending into the area of thewound 260 under the impermeable overlay 220 from a top drain portion 245b positioned within the port 227. In various embodiments, the top drainportion 245 b may be permanently or removably attached to the interiorsurface of the opening 228 of the port 227 using any suitable means,such as an adhesive, or by the top drain portion 245 b having a shapeadapted so that all or a portion of it fits tightly against all or aportion of the interior surface of the opening 228 in the port 227. Itis to be noted that the top drain portion 245 b must be sufficientlysealed against the surface of the port 227 in a manner so that reducedpressure can be maintained in the volume under the impermeable overlay220 in the area of the wound 260. In the embodiment illustrated in FIG.3, the top drain portion 245 b and the bottom drain portion 245 a of thesuction drain 245 are comprised of polymer tubing that is flexibleenough to allow the tubing to easily bend, but rigid enough to preventthe tubing from collapsing during use. In other embodiments, portions ofthe top drain portion 245 b and the bottom drain portion 245 a of thesuction drain 245 may be comprised of other materials, such as flexibleor semi-rigid polymers, plastics, rubber, silicone, or combinations ofsuch materials. In yet other embodiments, the suction drain 245 may havedifferent cross-sectional shapes, such as elliptical, square,rectangular, pentagonal, hexagonal, or other shapes, as long as thesuction drain 245 is adapted to provide an approximately hermetic sealwith the port 227, as described in more detail above. In still otherembodiments, the bottom drain portion 245 a of the suction drain 245 maybe further comprised of wound suction means that may be used to removedebris, exudate and other matter from the wound 260. In the embodimentillustrated in FIG. 3, the wound suction means is comprised of a distalend portion 245 a′ of the tubing comprising the bottom drain portion 245a having a plurality of perforations 245 a″ in the surface of the distalend portion 245 a′. In other embodiments, the distal end portion 245 a′of the bottom drain portion 245 a may have almost any shape orcombination of shapes (e.g., circular, elliptical, square, pentagonal,or hexagonal), including a shape different from the remaining portion ofthe bottom drain portion 245 a, may be of almost any size relative tothe remaining bottom drain portion 245 a (e.g., may be longer or shorterthan the remaining bottom drain portion 245 a or have a cross-sectionsmaller or larger than the remaining bottom drain portion 245 a, orboth), may have more or fewer perforations 245 a″, may have differentsizes and shapes of perforations 245 a″, may extend along differentportions of the bottom drain portion 245 a, and may be constructed inwhole or in part of materials that are not flexible. In embodiments thathave a distal end portion 245 a′, the distal end portion 245 a′ may beattached to the remaining portion of the bottom drain portion 245 a inalmost any manner, as long as the remaining bottom drain portion 245 ais in fluid communication with the wound suction means 245 a′. Examplesinclude an adhesive in some embodiments and a fastening collar in otherembodiments. In still other embodiments, the distal end portion 245 a′may be fused or welded to the remaining portion of the bottom drainportion 245 a. In yet other embodiments, the distal end portion 245 a′and the remaining portion of the bottom drain portion 245 a may befabricated as a single piece.

In some embodiments, as illustrated in FIG. 3, the top drain portion 245b may extend beyond the top of the port 227 into the area outside thevolume of the flexible overlay 220. In some of these embodiments, as isalso illustrated in FIG. 3, the suction drain connection means, whichmay be used to removably connect the reduced pressure supply means 240to the top drain portion 245 b of the suction drain 245 is a variabledescending diameter adapter 246 (commonly referred to as a “Christmastree” adapter) that is placed into the interior volume of the top drainportion 245 b at its distal end. In other embodiments, the suction drainconnection means may be clamps, fastening collars, or other fasteners orcombinations thereof. In yet other embodiments, the top drain portion245 b may be fused or welded to the reduced pressure supply means 240.In still other embodiments, the top drain portion 245 b and the portionof the reduced pressure supply means 240 adjacent to the top drainportion 245 b may be fabricated as a single piece. In other embodiments,the top drain portion 245 b may not extend beyond the top of the port227 and the reduced pressure supply means 240 may connect directly tothe port 227 using any suitable means, such as an adhesive, welding,fusing, clamps, collars or other fasteners, or any combination of suchmeans.

In the embodiment illustrated in FIG. 3, the distal end portion 245 a′of the suction drain 245 extends into the interior volume of the woundpacking means 278. In this embodiment, the wound packing means 278 andthe suction drain 245 may be fabricated by snaking the distal endportion 245 a′ of the suction drain 245 through an internal passagewayin the wound packing means 278, such as by pulling the distal endportion 245 a′ of the suction drain 245 through the passageway usingforceps. Alternatively, the wound packing means 278 and the suctiondrain 245 may be manufactured as a single piece in sterile conditionsand then be stored in an aseptic package until ready for use. In otherembodiments, the distal end portion 245 a′ of the suction drain 245 maybe placed adjacent or close to the wound packing means 278 in the areaof the wound 260. The preferred means of placement of the suction drain245 relative to the wound packing means 278 is dependent upon the typeof wound 260, the wound packing means 278, and the type of treatmentdesired. Referring to FIG. 3 as an example, it is therefore to be notedthat in some embodiments, the wound treatment device 215 may utilize asuction drain 245 without utilizing wound packing means 278, while inother embodiments a suction drain 245 may be utilized with wound packingmeans 278. In addition, in other embodiments, the wound treatment device215 may utilize wound packing means 278 without utilizing a suctiondrain 245, while in other embodiments wound packing means 278 may beutilized with a suction drain 245.

In the embodiment illustrated in FIG. 3, the vacuum system 250, which inconjunction with the wound treatment device 215 also represents anotherembodiment of the invention, is generally comprised of a suction bulb281 having an inlet port 282 and an outlet port 283, a bulb connectiontubing member 284, an exhaust tubing member 285, an exhaust controlvalve 286, a filter 287, and a supplemental vacuum system (illustratedschematically and generally designated 250 a). In this embodiment, thesuction bulb 281 is a hollow sphere that may be used to produce a supplyof reduced pressure for use with the wound treatment device 215. Inaddition, the suction bulb 281 may also be used to receive and storefluid aspirated from the wound 260. The inlet port 282 of the suctionbulb 281 is connected to one end of the bulb connection tubing member284, which is also the reduced pressure supply means 240 in thisembodiment. The connection tubing member 284 is connected by suctiondrain connection means to the top drain portion 245 b at its other endin a manner so that the interior volume of the suction bulb 281 is influid communication with the suction drain 245. In this embodiment, thebulb connection tubing member 284 is sufficiently flexible to permitmovement of the bulb connection tubing member 284, but is sufficientlyrigid to resist constriction when reduced pressure is supplied to thesuction drain 245 or when the location of the wound 260 is such that thepatient must sit or lie upon the bulb connection tubing member 284 orupon the wound treatment device 215. The outlet port 283 of the suctionbulb 281 is connected to the exhaust tubing member 285. In thisembodiment, the exhaust tubing member 285 is sufficiently flexible topermit movement of the exhaust tubing member 285, but is sufficientlyrigid to resist constriction when reduced pressure is supplied to thesuction drain 245. The inlet port 282 of the suction bulb 281 may beconnected to the bulb connection tubing member 284 and the outlet port283 of the suction bulb 281 may be connected to the exhaust tubingmember 285 using any suitable means, such as by welding, fusing,adhesives, clamps, or any combination of such means. In addition, insome embodiments, the suction bulb 281, the bulb connection tubingmember 284, and the exhaust tubing member 285 may be fabricated as asingle piece. In the illustrated embodiment, the exhaust control valve286 and the filter 287 are operably connected to the exhaust tubingmember 285. In this embodiment, the exhaust control valve 286 is used toregulate the flow of fluids (gases and liquids) to and from the suctionbulb 281 and the supplemental vacuum system 250 a. In embodiments of theinvention that do not have a supplemental vacuum system 250 a, theexhaust control valve 286 regulates flow of fluids to and from thesuction bulb 281 and the outside atmosphere. Generally, the exhaustcontrol valve 286 allows fluids to flow out of the suction bulb 281through the outlet port 283, but not to flow in the reverse directionunless permitted by the user of the appliance 210. Any type of flowcontrol valve may be used as the exhaust control valve 286, as long asthe valve is capable of operating in the anticipated environmentinvolving reduced pressure and wound 260 exudate. Such valves are wellknown in the relevant art, such as sprung and unsprung flapper-typevalves and disc-type valves. In this embodiment, the filter 287 isoperably attached to the exhaust tubing member 285 between the outletport 283 of the suction bulb 281 and the exhaust control valve 286. Thefilter 287 prevents potentially pathogenic microbes or aerosols fromcontaminating the exhaust control valve 286 (and supplemental vacuumsystem 250 a), and then being vented to atmosphere. The filter 287 maybe any suitable type of filter, such as a micropore filter. In otherembodiments, the filter 287 may also be a hydrophobic filter thatprevents any exudate from the wound 260 from contaminating the exhaustcontrol valve 286 (and the supplemental vacuum system 250 a) and thenbeing vented to atmosphere. In still other embodiments, the filter 287may perform both functions. It is to be noted, however, that the outletport 283, the exhaust control valve 286, the filter 287, or anycombination of the exhaust control valve 286 and the filter 287, neednot be utilized in connection with the vacuum system 250 in otherembodiments of the invention.

In some embodiments of the invention illustrated in FIG. 3 that do notutilize a supplemental vacuum system 250 a, the suction bulb 281 may beused to produce a supply of reduced pressure in the following manner.First, the user of the appliance 210 appropriately seals all of thecomponent parts of the appliance 210 in the manner described herein. Forexample, the impermeable overlay 220 is sealed (or placed adjacent) tothe body 170 and the suction drain 245 is sealed to the bulb connectiontubing member 284 and the surface of the port 227. The user then opensthe exhaust control valve 286 and applies force to the outside surfaceof the suction bulb 281, deforming it in a manner that causes itsinterior volume to be reduced. When the suction bulb 281 is deformed,the gas in the interior volume is expelled to atmosphere through theoutlet port 283, the exhaust tubing member 285, the filter 287, and theexhaust control valve 286. The user then closes the exhaust controlvalve 286 and releases the force on the suction bulb 286. The suctionbulb 281 then expands, drawing fluid from the area of the wound 260under the wound treatment device 215 into the suction bulb 281 throughthe suction drain 245 and causing the pressure in such area to decrease.To release the reduced pressure, the user of the appliance 210 may openthe exhaust control valve 286, allowing atmospheric air into theinterior volume of the suction bulb 281. The level of reduced pressuremay also be regulated by momentarily opening the exhaust control valve286.

The suction bulb 281 may be constructed of almost any fluid impermeableflexible or semi-rigid material that is suitable for medical use andthat can be readily deformed by application of pressure to the outsidesurface of the suction bulb 281 by users of the appliance 210 and stillreturn to its original shape upon release of the pressure. For example,the suction bulb 281 may be constructed of rubber, neoprene, silicone,or other flexible or semi-rigid polymers, or any combination of all suchmaterials. In addition, the suction bulb 281 may be of almost any shape,such as cubical, ellipsoidal, or polygonal. The suction bulb 281 mayalso be of varying size depending upon the anticipated use of thesuction bulb 281, the size of the wound treatment device 215, use of asupplemental vacuum system 250 a, the level of reduced pressure desired,and the preference of the user of the appliance 210. In the embodimentof the invention illustrated in FIG. 3, the supplemental vacuum system250 a is connected to the exhaust tubing member 285 and is used toprovide a supplemental supply of reduced pressure to the suction bulb281 and wound treatment device 215. In this embodiment, the supplementalvacuum system 250 a may have substantially the same structure, features,characteristics, and operation of the various embodiments of the vacuumsystem 50 described above and illustrated in connection with FIG. 2A andFIG. 2B. It is to be noted, however, that the supplemental vacuum system250 a need not be used in connection with the vacuum system 280 in otherembodiments of the invention.

Except as described below, the wound treatment appliance 210 describedabove and illustrated in connection with FIG. 3 may generally be used ina manner similar to the wound treatment appliance 110 described aboveand illustrated in connection with FIG. 2A and FIG. 2B. As a result,except as described below, the example of how the embodiment of thewound treatment appliance 110 and the flexible overlay 120 describedabove and illustrated in connection FIG. 2A may be used in treatment ofa wound 160 also applies to the embodiment of the appliance 210described above and illustrated in connection with FIG. 3. In the caseof the embodiment illustrated in FIG. 3, however, the wound packingmeans 278 is placed into the wound 260 prior to placement of theflexible overlay 220 over the portion of the wound 260 to be treated. Inaddition, the flexible overlay 220 is placed over the wound packingmeans 278. In embodiments where the distal end portion 245 a′ of asuction drain 245 is placed into the interior volume of, or adjacent to,the wound packing means 278, the distal end portion 245 a′ of thesuction drain 245 is also placed in the appropriate position before theflexible overlay 220 is placed over the wound 260. In embodimentsutilizing a suction drain 245 without wound packing means 278, thesuction drain 245 is installed in the flexible overlay 220 before theflexible overlay 220 is placed over the wound 260.

Another embodiment of the invention is the wound treatment appliance 310illustrated in FIG. 4. FIG. 4 also illustrates another example of howthe embodiment of the flexible overlay 20 described above andillustrated in connection with FIG. 1A may be used to provide reducedpressure treatment for a wound 360 on the body 370 of a patient. In thisembodiment, the wound treatment appliance 310 is comprised of a flexibleoverlay 320 and a vacuum system, generally designated 350, that isoperably connected to, and provides a supply of reduced pressure to, theflexible overlay 320. In addition, in this embodiment, the vacuum system350 is further comprised of a reduced pressure supply source, generallydesignated 330, which is described in more detail below, and reducedpressure supply means, generally designated 340, which are described inmore detail below. In this embodiment, the reduced pressure supply means340 are used to connect the reduced pressure supply source 330 to theflexible overlay 320 in a manner so that reduced pressure is supplied tothe area under the flexible overlay 320, as described in more detailbelow. In the embodiment illustrated in FIG. 4, the flexible overlay 320has substantially the same structure, features, and characteristics asthe flexible overlay 20 described above and illustrated in connectionwith FIG. 1A. It is to be noted, however, that in other embodiments, theflexible overlay 320 may have substantially the same structure,features, and characteristics as any embodiment of all of the flexibleoverlays 20, 20 a, 20 b, 20 c of the other embodiments described aboveand illustrated in connection with FIG. 1A, FIG. 1B, FIG. 1C, and FIG.1D, respectively. In this example, the flexible overlay 320 is placedover and encloses the entire wound 360, which is at the distal end of anamputated limb. It is to be noted that in other embodiments, theappliance 310 may also be comprised of tissue protection means 375,which may be substantially the same as the tissue protection means 175of the embodiment described above and illustrated in connection withFIG. 2A. In other embodiments, the appliance 310 may also be comprisedof wound packing means (not illustrated), which may be substantially thesame as the wound packing means 278 of the embodiment described aboveand illustrated in connection with FIG. 3.

In the embodiment illustrated in FIG. 4, the reduced pressure supplysource 330 of the vacuum system 350, which produces a source of reducedpressure or suction that is supplied to the flexible overlay 320,includes a small, portable vacuum pump 331, a filter 333, and a powersource (not illustrated) that is contained within the housing for theportable vacuum pump 331. In the illustrated embodiment, predeterminedamounts of suction or reduced pressure are produced by the portablevacuum pump 331. The portable vacuum pump 331 is preferably controlledby a control device (not illustrated) that is also located within thehousing for the portable vacuum pump 331, which may providesubstantially the same functions as the control device 132 describedabove and illustrated in connection with FIG. 2A and FIG. 2B. Except forits smaller size, the portable vacuum pump 331 may operate insubstantially the same manner as the vacuum pump 131 of the inventiondescribed above and illustrated in connection with FIG. 2A and FIG. 2B.In the embodiment illustrated in FIG. 4, the filter 333 may have thesame structure, features, characteristics, and operation, and providesubstantially the same functions, as the filter 133 described above andillustrated in connection with FIG. 2A and FIG. 2B. The power source maybe any source of energy currently known in the art or that may bedeveloped in the art in the future that may be used to power theportable vacuum pump 331. For example, in some embodiments, the powersource may be a fuel cell, battery or connection to a standardelectrical outlet. In the illustrated embodiment, the filter 333 isrigidly connected to the portable vacuum pump 331. It is to be notedthat in other embodiments, the reduced pressure supply source 330 maynot have a filter 333.

In the embodiment illustrated in FIG. 4, the reduced pressure supplymeans 340 of the vacuum system 350, which is used to connect the reducedpressure supply source 330 to a port 327 on the flexible overlay 320 sothat reduced pressure is supplied to the area of the wound 360 under theflexible overlay 320, is comprised of at least one tubing member 341. Inthis embodiment, the at least one tubing member 341 is a rigid tubingmember. In other embodiments, the at least one tubing member 341 may besufficiently flexible to permit movement of the at least one tubingmember 341, but is sufficiently rigid to resist constriction whenreduced pressure is supplied to the port 327 or when the location of thewound 360 is such that the patient must sit or lie upon the at least onetubing member 341 or upon the flexible overlay 320. In the embodimentillustrated in FIG. 4, the at least one tubing member 341 is connectedto the port 327 by inserting one end of the at least one tubing member341 into an opening 328 in the port 484 and sealing (such as with anadhesive) the at least one tubing member 341 to the port 327. It is tobe noted that in other embodiments, the at least one tubing member 341may be connected to the port 327 using any suitable means currentlyknown in the relevant art or developed in the relevant art in thefuture. Examples include the suction drain connection means of theembodiment discussed above and illustrated in connection with FIG. 3.Similar means may be used to connect the other end of the at least onetubing member 341 to the reduced pressure supply source 330 providingthe reduced pressure. In other embodiments, the reduced pressure supplymeans 340 may further comprise a fluid collection system (notillustrated), which may generally have the same structure, features,characteristics, and operation, and perform the same functions, as thefluid collection system 142 of the embodiment described above andillustrated in connection with FIG. 2A and FIG. 2B.

Another embodiment of the current invention is the wound treatmentappliance 410 illustrated in FIG. 5. In this embodiment, the appliance410 is comprised of a wound treatment device 415, which is furthercomprised of a flexible overlay 420, a collection chamber 490 to receiveand hold fluid aspirated from the wound 460, collection chamberattachment means to operably attach the collection chamber 490 to theoverlay 420, as described in more detail below, and reduced pressuresupply means, generally designated 440, which are described in moredetail below. In this embodiment, the flexible overlay 420 is adapted tobe placed over and enclose all or a portion of the wound 460 in the samemanner as the flexible overlay 20 described in detail above andillustrated in connection with FIG. 1A. It is to be noted, however, thatthe flexible overlay 420 illustrated in FIG. 5 is shown in position onthe body 470 over the wound 460, but not in its collapsed state. In theillustrated embodiment, and except as described in more detail below,the flexible overlay 420 has substantially the same structure, featuresand characteristics as the flexible overlay 20 described in detail aboveand illustrated in connection with FIG. 1A. In various embodiments,except as described in more detail below, the flexible overlay 420 mayhave substantially the same structure, features, characteristics andoperation as the embodiments of the flexible overlays 20, 20 a, 20 b, 20c, 120, 220 described in more detail above and illustrated in connectionwith FIG. 1A, FIG. 1B, FIG. 1C, FIG. 1D, FIG. 2A, and FIG. 3,respectively. In addition, the overlay 420 may be almost any type ofsemi-rigid or rigid wound covering apparatus currently known in therelevant art or that may be developed in the relevant art in the futurethat has a port and is designed to cover and enclose a wound andmaintain reduced pressure in the area of the wound under the woundcovering apparatus. For example, the overlay 420 may generally havesubstantially the same structure, features and characteristics as theembodiments of the rigid or semi-rigid generally conically-shaped orcup-shaped wound covers described in U.S. patent application Ser. No.10/652,100, which was filed by the present inventor with the U.S. Patentand Trademark Office on Aug. 28, 2003, and published as U.S. PublicationNo. 2004/0073151 A1, and U.S. patent application Ser. No. 11/026,733,now U.S. Pat. No. 7,128,735, entitled “Improved Reduced Pressure WoundTreatment Appliance,” which was filed by the present inventor with theU.S. Patent and Trademark Office on Dec. 30, 2004, the disclosures ofwhich are incorporated herein by reference. In the illustratedembodiment, reduced pressure supply means, generally designated 440,which are described in more detail below, are used to operably connectthe collection chamber 490 to a reduced pressure supply source,generally designated 430, which is described in more detail below, thatprovides a supply of reduced pressure to the collection chamber 490, sothat the volume within the collection chamber 490 and under the flexibleoverlay 420 in the area of the wound 460 to be treated are supplied withreduced pressure by the reduced pressure supply source 430. Together,the reduced pressure supply means 440 and the reduced pressure supplysource 430 comprise a vacuum system, generally designated 450. Invarious embodiments, except as described in more detail below, thereduced pressure supply means 440 used to connect the reduced pressuresupply source 430 to the collection chamber 490 may have substantiallythe same structure, features, characteristics, and operation as thereduced pressure supply means 140, 240, 340 described above andillustrated in connection with FIG. 2A, FIG. 2B, FIG. 3, and FIG. 4,respectively. In addition, in various embodiments, except as describedin more detail below, the reduced pressure supply source 430 used toprovide the supply of reduced pressure to the collection chamber 490 mayhave substantially the same structure, features, characteristics, andoperation as the reduced pressure supply source 130, 280, 330 describedabove and illustrated in connection with FIG. 2A, FIG. 2B, FIG. 3, andFIG. 4, respectively.

In the embodiment of the appliance 410 illustrated in FIG. 5, thecollection chamber 490 is approximately cylindrical in shape. In otherembodiments, the collection chamber 490 may have other shapes. Forexample, the collection chamber may be shaped approximately as a sphere,ellipsoid, cube, polyhedron, or other shape or combination of suchshapes, as long as the collection chamber 490 has an interior volume toreceive and hold fluid aspirated from the wound 460. The collectionchamber 490 may also be of almost any size. For example, the collectionchamber 490 may be relatively small where the wound 460 is expected toaspirate only a small volume of fluid. On the other hand, the collectionchamber 490 may be relatively large where it is expected that the wound460 will aspirate a large volume of fluid. As a result, the preferredsize of the collection chamber 490 is dependent upon the size of thewound 460 to be treated, the size of the flexible overlay 420, the typeof wound 460 to be treated, and the preference of the user of theappliance 410. In various embodiments, the collection chamber 490 may becomprised of almost any medical grade material that is currently knownin the art or that may be developed in the art in the future, as long assuch material is fluid-impermeable and suitable for purposes of woundtreatment (e.g., can be sterilized and does not absorb significantamounts of wound 460 exudate). For example, the collection chamber 490may be comprised of rubber (including neoprene) and polymer materials,such as silicone, silicone blends, silicon substitutes, polyvinylchloride, polycarbonates, polyester-polycarbonate blends, or a similarpolymer, or combinations of all such materials. It is to be noted thatthe collection chamber 490 may have a rigid or semi-rigid structure insome embodiments. In other embodiments, the collection chamber 490 maybe more flexible so that it can be squeezed in a manner similar to thesuction bulb 281, as described above and illustrated in connection withFIG. 3. Although the collection chamber 490 may be constructed of amaterial different from the material comprising the flexible overlay 420in various embodiments of the invention, the collection chamber 490 ispreferably constructed from the same material comprising the flexibleoverlay 420. The collection chamber 490 may be constructed using anysuitable means currently known in the art or that may be developed inthe art in the future. For example, a collection chamber 490 constructedof silicone may be manufactured by means of injection molding.

In various embodiments, the collection chamber attachment means operablyattaches the collection chamber 490 to the flexible overlay 420 in amanner so that exudate and reduced pressure are permitted to flowbetween the collection chamber 490 and the volume under the flexibleoverlay 420 in the area of the wound 460. Also, in various embodiments,as illustrated by the appliance 410 in FIG. 5, the collection chamber490 is positioned approximately adjacent to the flexible overlay 420 onthe side of the flexible overlay 420 opposite the wound 460. Althoughthe collection chamber 490 and the collection chamber attachment meansare positioned approximately at the apex of the flexible overlay 420 inthe illustrated embodiment, in other embodiments the collection chamber490 and collection chamber attachment means may be positioned at almostany location on the surface of the impermeable overlay 420 opposite thewound 460, as long as the collection chamber 490 and collection chamberattachment means do not materially interfere with the operation of theflexible overlay 420. As illustrated in FIG. 5, the collection chamberattachment means may be a rigid or semi-rigid connecting member 491between the collection chamber 490 and the flexible overlay 420. In thisembodiment, the connecting member 491 is approximately cylindrical inshape and has a port 492 therein, which is also approximatelycylindrical in shape and extends between the collection chamber 490 andthe flexible overlay 420 so that fluids can flow between the collectionchamber 490 and the flexible overlay 420. In other embodiments, theconnecting member 491 and the port 492 may be of almost any shape orcombination of shapes. For example, the connecting member 491 and theport 492 may be shaped approximately as a sphere, ellipsoid, cube,polygon, paraboloid, or any other shape or combination of shapes, aslong as the connecting member 491 provides a rigid or semi-rigidconnection between the collection chamber 490 and the flexible overlay420 that is adequate to support the collection chamber 490 when it isfilled with exudate from the wound 460, and the port 492 is of a sizeand shape adequate to allow the flow of exudate from the wound 460between the collection chamber 490 and the flexible overlay 420. Forexample, the collection chamber 490 in some embodiments may haveapproximately the same outside diameter as the connecting member 491, asillustrated by the phantom lines 493 in FIG. 5. The connecting member491 may generally be constructed of any material that is suitable forconstruction of the collection chamber 490 or the flexible overlay 420,and is preferably constructed from the same materials as the collectionchamber 490 and the flexible overlay 420. In various embodiments, thecollection chamber 490 and the flexible overlay 420 may be connected tothe connecting member 491 using any suitable means, such as byadhesives, welding, fusing, clamps, and other fastening means orcombinations of such means. In yet other embodiments, the collectionchamber 490, the flexible overlay 420, and the connecting member 491 maybe fabricated as a single piece. In still other embodiments, one or moreof the connections between the collection chamber 490, the flexibleoverlay 420, and the connecting member 491 may provide for removing onecomponent from another to empty fluid from the collection chamber 490.For example, the collection chamber 490, the flexible overlay 420, andthe connecting member 491 may each be threaded at their points ofconnection so that they can be screwed together and then unscrewed whendesired. In still other embodiments, the collection chamber 490 and theflexible overlay 420 may be directly connected together without aconnecting member 491, as long as the connection allows fluid to flowbetween the collection chamber 490 and the flexible overlay 420. Suchconnection may be made using any of the means described above in thisparagraph.

In some embodiments, as illustrated in FIG. 5, the connecting member491, as the collection chamber attachment means, may be furthercomprised of a flow control means, which is described in more detailbelow, operably positioned between the collection chamber 490 and theflexible overlay 420. In these embodiments, the flow control meanspermits fluid aspirated from the wound 460 to flow from the volume underthe flexible overlay 420 in the area of the wound 460 through the port492 into the collection chamber 490, but not in the opposite direction.In the illustrated embodiment, the flow control means is comprised of aflapper-type valve 494. In this embodiment, the valve 494 has twoflapper members 494 a that are hinged at their distal end to a portionof the connecting member 491, and the flapper members 494 a are of ashape and size adapted to substantially close the port 492 when they arepositioned in the closed position. In other embodiments, the flowcontrol means may be comprised of a disc-type valve, wherein the disc ofthe valve moves with the flow of fluids and contacts a seat disposedaround the perimeter of the port when the flow of fluids is misdirected,so that the port is sealed closed and prevents fluid flow in the wrongdirection. In some embodiments, as illustrated in FIG. 5, the collectionchamber 490 may be further comprised of a shroud 495 (illustrated by thephantom lines) that extends from a portion of the collection chamber 490to the flexible overlay 420. In these embodiments, the shroud 495 isapproximately tubular in shape. In other embodiments, the shroud 495 mayhave other shapes. The shroud 495 generally provides additional supportfor the collection chamber 490 and may also provide for a moreaesthetically pleasing appearance for the appliance 410. In addition, inthe embodiment of the appliance 410 illustrated in FIG. 5, the reducedpressure supply means 440 is connected to the collection chamber 490 bymeans of a stopper 445 adapted to fit into an opening 496 in thecollection chamber 490. The stopper 445 forms a seal with the portion ofthe collection chamber 490 adjacent to the opening 496 so that reducedpressure can be maintained within the interior volume of the collectionchamber 490. In this embodiment, the reduced pressure supply means iscomprised of a tubular member 441 that is positioned in a port 446 inthe stopper 445 at one end and is connected to the reduced pressuresupply source 430 at the other end.

The embodiment of the appliance 410 illustrated in FIG. 5 may be used totreat a wound 460 on a body 470 using a method comprising the followingsteps. First, the wound treatment device 415 is positioned on the body470 over the area of the wound 460 to be treated. Next, the vacuumsystem 450 is operably connected to the collection chamber 490. Theflexible overlay 420 may then be collapsed in the approximate directionof the wound 460 when reduced pressure is supplied to the volume underthe flexible overlay 420 in the area of the wound 460 so that anapproximately hermetic seal (as illustrated and described in more detailabove in connection with FIG. 2A) is formed between the flexible overlay420 and the body 470 in the area of the wound 460. Next, reducedpressure is maintained in the volume of the flexible overlay 420 in thearea of the wound 460 until the area of the wound 460 being treated hasprogressed toward a selected stage of healing. In other embodiments, themethod may further comprise the step of placing tissue protection means475, which may be substantially the same as the tissue protection means175, as described above and illustrated in connection with FIG. 2A, onthe tissue 471 of the body 470 that is to be approximately adjacent tothe flexible overlay 420, such step being performed prior to positioningthe flexible overlay 420 over the area of the wound 460 to be treated.In yet other embodiments, the method further comprises the step ofplacing wound packing means (not illustrated), which may besubstantially the same as the wound packing means 278, as describedabove and illustrated in connection with FIG. 3, between the wound 460and the impermeable overlay 420 in the area of the wound 460 to betreated, such step being performed prior to positioning the impermeableoverlay 420 over the area of the wound 460 to be treated. In still otherembodiments, the reduced pressure under the flexible overlay 420 in thearea of the wound 460 is in the range from approximately 20 mm of Hgbelow atmospheric pressure to approximately 125 mm of Hg belowatmospheric pressure. In other embodiments, the reduced pressure isapplied in a cyclic nature, the cyclic nature providing alternating timeperiods of application of reduced pressure and without application ofreduced pressure. In yet other embodiments, the method is furthercomprised of the step of emptying any fluid collected in the collectionchamber 490. This step may be performed after the flexible overlay 420is collapsed in the approximate direction of the wound 460 and may alsobe performed before or after the area of the wound 460 being treated hasprogressed toward a selected stage of healing.

Another embodiment of the invention is the wound treatment appliance 510illustrated in FIG. 6. In this embodiment, the appliance 510 iscomprised of a flexible overlay 520, a collection chamber 590 to receiveand hold fluid aspirated from a wound (not shown), collection chamberattachment means to operably attach the collection chamber 590 to theflexible overlay 520, as described in more detail below, and reducedpressure supply means, generally designated 540, which are described inmore detail below. In this embodiment, the flexible overlay 520 isadapted to be placed over and enclose all or a portion of a wound in thesame manner as the flexible overlay 20 a described in detail above andillustrated in connection with FIG. 1B. It is to be noted that theflexible overlay 520 illustrated in FIG. 6 is not shown in its collapsedstate. In the illustrated embodiment, and except as described in moredetail below, the flexible overlay 520 has substantially the samestructure, features, and characteristics as the flexible overlay 20 adescribed in detail above and illustrated in connection with FIG. 1B. Inother embodiments, the flexible overlay 520 may be of other shapes andhave other features. For example, the flexible overlay 520 may be of theshape and have the features illustrated and described above inconnection with the appliance 10 b and 10 c of FIG. 1C and FIG. 1D,respectively. In the embodiment illustrated in FIG. 6, the reducedpressure supply means 540, which are described in more detail below, maybe used to operably connect the collection chamber 590 to a reducedpressure supply source (not shown), which is described in more detailbelow, that provides a supply of reduced pressure to the collectionchamber 590, so that the volume within the collection chamber 590 andunder the flexible overlay 520 in the area of the wound to be treatedare supplied with reduced pressure by the reduced pressure supplysource. Together, the reduced pressure supply means 540 and the reducedpressure supply source comprise a vacuum system, generally designated550. In this embodiment, except as described in more detail below, thereduced pressure supply means 540 used to connect the reduced pressuresupply source to the collection chamber 590 may have substantially thesame structure, features, characteristics, and operation as the reducedpressure supply means 140, 240, 340 described above and illustrated inconnection with FIG. 2A, FIG. 2B, FIG. 3, and FIG. 4, respectively. Inaddition, in this embodiment, except as described in more detail below,the reduced pressure supply source used to provide the supply of reducedpressure to the collection chamber 590 may have substantially the samestructure, features, characteristics, and operation as the reducedpressure supply source 130, 280, 330 described above and illustrated inconnection with FIG. 2A, FIG. 2B, FIG. 3, and FIG. 4, respectively. Theembodiment of the appliance 510 illustrated in FIG. 6 may be used totreat a wound on a body using substantially the same method describedabove in connection with the appliance 410 illustrated in FIG. 5.

In the embodiment illustrated in FIG. 6, the collection chamber 590 ispositioned approximately adjacent to the flexible overlay 520 on theside of the flexible overlay 520 opposite the wound. In this embodiment,the collection chamber attachment means, as described in more detailbelow, is comprised of a membrane 591. In this embodiment, the membrane591 acts as a barrier separating the collection chamber 590 and theflexible overlay 520, so that the membrane 591 acts as a portion of thesurface of the collection chamber 590 and a portion of the surface ofthe flexible overlay 520. In addition, the membrane 591 has at least oneport 592 therein so that the volume within the collection chamber 590 isin fluid communication with the volume under the flexible overlay 520 inthe area of the wound. It is to be noted that there may be more than oneport 592 in other embodiments. The number of ports 492 is generallydependent upon the size and shape of the collection chamber 590, thesize and shape of the impermeable flexible overlay 520, the anticipatedamount of exudate to be aspirated from the wound, the level of reducedpressure to be utilized, and the individual preference of the user ofthe appliance 510. In embodiments where the flexible overlay 520 has anapproximately elongated conical shape, as illustrated in FIG. 6, theflexible overlay 520 may have a base end opening 521 and a top endopening 524 opposite the base end opening 521. In these embodiments, thebase end opening 521 may have an either approximately circular shape orapproximately elliptical shape sized to be placed over and enclose thearea of the wound to be treated. The top end opening 524 may have eitheran approximately circular shape or approximately elliptical shape. Inthe illustrated embodiments, the membrane 591 is adapted to be of thesame shape and size as the top end opening 524 and the membrane 591 ispositioned so that it is attached to the entire perimeter of the top endopening 524 and covers the entire top end opening 524. The membrane 591may be attached to the perimeter of the top end opening 524 by anysuitable means currently known in the relevant art or developed in theart in the future. Examples of such means include welding or fusing themembrane 591 to the perimeter of the top end opening 524. Alternatively,the membrane 591 may be fabricated as a single piece with the flexibleoverlay 520.

In the embodiment of the appliance 510 illustrated in FIG. 6, thecollection chamber 590 has an approximately elongated conical shape, achamber bottom end opening 593, and a reduced pressure supply port 596positioned at the apex of the collection chamber 590 opposite thechamber bottom end opening 593. The reduced pressure supply port 596 maybe used to operably connect the reduced pressure supply means 540 to thecollection chamber 590. In some embodiments, a micropore or hydrophobicfilter or both (not shown) may be operably positioned within the reducedpressure supply port 596 or the connection with the reduced pressuresupply means 540 to retain the exudate from the wound within thecollection container 590 or to prevent exudate from contaminatingportions of the vacuum system 550, or both. In the illustratedembodiment, the chamber bottom end opening 593 is adapted to be ofapproximately the same size and shape as the top end opening 524 of theimpermeable flexible overlay 520. In other embodiments, the collectionchamber 590 may be of other shapes and sizes and its bottom end opening593 may not necessarily be of the same size and shape as the top endopening 524 of the flexible overlay 520. In all embodiments, however,the collection chamber 590 is attached to the membrane 591 in a mannerso that the membrane 591 acts as a portion of the surface of thecollection chamber 590 and so that the volume within the collectionchamber 590 is airtight, except for the at least one port 592 and thereduced pressure supply port 596. In one embodiment, the collectionchamber 590 and the flexible overlay 520 have the shapes illustrated inFIG. 6. The membrane 591 may be attached to the perimeter of the chamberbottom end opening 593 by any suitable means currently known in therelevant art or developed in the art in the future. Examples of suchmeans include welding or fusing the membrane 591 to the perimeter of thechamber bottom end opening 593. Alternatively, the membrane 591 or theflexible overlay 520, or both, may be fabricated as a single piece withthe collection chamber 590. The preferred shapes and sizes of thecollection chamber 590 and the flexible overlay 520 are dependent uponthe size and type of wound to be treated, the area of the body on whichthe wound is positioned, the level of reduced pressure to be utilized,the amount of collapse of the flexible overlay 520 desired, and thepreference of the user of the appliance 510. In this embodiment of theinvention, the collection chamber 590 may be comprised of almost anymedical grade material that is currently known in the art or that may bedeveloped in the art in the future, as long as such material isfluid-impermeable and suitable for purposes of wound treatment (e.g.,can be sterilized and does not absorb significant amounts of woundexudate). For example, the collection chamber 590 may be comprised ofrubber (including neoprene) and flexible polymer materials, such assilicone, silicone blends, silicone substitutes, polyvinyl chloride,polycarbonates, polyester-polycarbonate blends, or a similar polymer, orcombinations of all such materials. It is to be noted that thecollection chamber 590 may have a rigid or semi-rigid structure in someembodiments. In other embodiments, the collection chamber 590 may bemore flexible so that it can be squeezed in a manner similar to thesuction bulb 281, as described above and illustrated in connection withFIG. 3. Although the collection chamber 590 may be constructed of amaterial different from the material comprising the flexible overlay 520in various embodiments of the invention, the collection chamber 590 ispreferably constructed from the same material comprising the flexibleoverlay 520. The collection chamber 590 may be constructed using anysuitable means currently known in the art or that may be developed inthe art in the future. For example, a collection chamber 590 constructedof silicone may be manufactured by means of injection molding.

In the embodiment illustrated in FIG. 6, the membrane 591 and its meansof being sealed to the perimeters of the top end opening 524 and thechamber bottom end opening 593, together as collection chamberattachment means, operably attach the collection chamber 590 to theimpermeable overlay 520 in a manner so that exudate and reduced pressureare permitted to flow between the collection chamber 590 and the volumeunder the impermeable overlay 520 in the area of the wound. In theembodiment illustrated in FIG. 6, the at least one port 592 isapproximately cylindrical in shape and extends between the collectionchamber 590 and the flexible overlay 520 so that fluids can flow betweenthe collection chamber 590 and the flexible overlay 520. In otherembodiments, the at least one port 592 may be of almost any shape orcombination of shapes. In some embodiments, as illustrated in FIG. 6,the membrane 591 comprising the collection chamber attachment means maybe further comprised of a flow control means, which is described in moredetail below, operably connected with the at least one port 592 andpositioned between the collection chamber 590 and the flexible overlay520. In these embodiments, the flow control means permits fluidaspirated from the wound to flow from the volume under the flexibleoverlay 520 in the area of the wound 560 through the at least one port592 into the collection chamber 590, but not in the opposite direction.In the illustrated embodiment, the flow control means is comprised of aflapper-type valve 594. In this embodiment, the valve 594 has twoflapper members 594 a that are hinged at their distal end to a portionof the membrane 491 or supporting structure surrounding the at least oneport 492 and the flapper members 594 a are of a shape and size adaptedto substantially close the at least one port 592 when they arepositioned in the closed position. In other embodiments, the flowcontrol means may be comprised of a disc-type of valve.

One embodiment of the invention is the treatment appliance 1010illustrated in FIG. 7. FIG. 7 is an exploded perspective view of a cover1020 comprising the treatment appliance 1010 from the side of and abovethe cover 1020 as it appears when applied to a portion of the body 1016of a patient surrounding a wound 1015. In this embodiment, the cover1020 is comprised of a top cup member 1021, an interface member 1022,and interface attachment means, which are described in more detailbelow, to attach the interface member 1022 to the top cup member 1021.This embodiment also comprises sealing means to seal the cover 1020 tothe portion of the body 1016 surrounding the wound 1015, which aredescribed in more detail below, and reduced pressure supply means (notillustrated), which are also described in more detail below. The cover1020 is generally sized to be placed over and enclose the wound 1015 tobe treated. The cover 1020 and the sealing means (described in moredetail below) allow reduced pressure to be maintained in the volumeunder the cover 1020 at the site of the wound 1015 to be treated, asdescribed in more detail below. The reduced pressure supply means areused to operably connect the cover 1020 to a reduced pressure supplysource (also not illustrated) in a manner so that the reduced pressuresupply source provides a supply of reduced pressure to the cover 1020,so that the volume under the cover 1020 at the site of the wound may bemaintained at reduced pressure. It is to be noted, however, that inother embodiments of the present invention, the top cup member 1021 maybe used for treatment of a wound 1015 without the interface member 1022.In these embodiments, the top cup member 1021 alone is placed over thewound 1015 and reduced pressure is applied to the volume under the topcup member 1021.

The embodiment of the top cup member 1021 of the cover 1020 illustratedin FIG. 7 is further comprised of a lid member 1023 and a cup bodymember 1024. In this embodiment, the lid member 1023 is removably orpermanently attached to the cup body member 1024 using lid attachmentmeans, which may be substantially the same as any of the interfaceattachment means, which are described in more detail below. While thelid member 1023 is attached to the cup body member 1024, the lidattachment means provides a gas-tight and liquid-tight seal so thatreduced pressure may be maintained in the volume under the cover 1020 inthe area of the wound 1015. In the embodiment illustrated in FIG. 7, thetop cup member 1021 is approximately cylindrical in shape. In otherembodiments, the top cup member 21 may be of almost any shape orcombination of shapes, as long as the open end 1023 a of the lid member1023 is of a size and shape adapted to fit against a portion of thesurface of the cup body member 1024 in a manner so that an airtight andliquid-tight seal can be maintained by the use of the lid attachmentmeans, as described in more detail below. For example, as illustrated inFIG. 11, the top cup member 10121 of the cover 10120 may beapproximately cup-shaped, having an interface member 10122 disposed onits bottom surface. As other examples, the cover 1020, 10120 may becubical, spherical, spheroidal, hexahedral, polyhedral, or arcuate inshape, or may be comprised of any combination of such shapes, in otherembodiments. Thus, referring again to FIG. 7 as an example, the lidmember 1023 may also be shaped approximately as a hemisphere or a conein other embodiments. As another example, in yet other embodiments, thecup body member 1024 and the open end 1023 a of the lid member 1023 mayhave a cross-section of approximately elliptical, square, rectangular,polygonal, arcuate or other shape or combination of all such shapes. Thepreferred shape and size of the top cup member 1021, 10121, as well asthe size and shape of any lid member 1023 comprising it, are dependentupon the materials comprising the cover 1020, 10120, the thickness ofthe cover 1020, 10120, the nature of the wound to be treated, the size,shape and contour of the portion of the body to be covered by the cover1020, 10120, the magnitude of the reduced pressure to be maintainedunder the cover 1020, 10120, the size, shape and other aspects of theinterface portion 1022, 10122, the individual preferences of the user ofthe cover 1020, 10120, and other factors related to access to the wound1015, the sealing means, and the reduced pressure supply means, asdescribed in more detail below.

In the embodiment of the cover 1020 illustrated in FIG. 7, the lidmember 1023 may be detached from the cup body member 1024. This allowsthe user of the appliance 1010 to have access to the area of the wound1015 without having to break the sealing means used to operably seal thecover 1020 to the portion of the body 1016 surrounding the wound 1015.The ability to access the wound 1015 in this manner results in moreefficient use of the time of healthcare practitioners and lessdiscomfort to patients. It is to be noted that in other embodiments, thelid member 1023 and the cup body member 1024 may be permanently attachedtogether or may be formed as a single piece. For example, the top cupmember 10121 of the cover 10120 of FIG. 11 does not have a detachablelid member, but is instead formed as a single piece. In theseembodiments, and referring to the cover 1020 of FIG. 7 as an example,the lid member 1023 and the cup body member 1024 may be fabricated as asingle piece, such as by injection molding, or they may be attachedtogether by any appropriate means, such as by welding, fusing,adhesives, glues, bolts, screws, pins, rivets, clamps, or otherfasteners or means or combinations of all such means. In the embodimentof the present invention illustrated in FIG. 7, the lid member 1023 andthe cup body member 1024 are each constructed of a material that isrigid enough to support the cover 1020 away from the wound 1015. Thus,the lid member 1023 and the cup body member 1024 of the cover 1020 maybe comprised of almost any rigid or semi-rigid medical grade materialthat is currently known in the art or that may be developed in the artin the future, as long as such material is liquid-impermeable, suitablefor purposes of wound treatment (e.g., can be sterilized and does notabsorb significant amounts of fluids, such as wound exudate), and iscapable of supporting the cover 1020 away from the wound 1015. Forexample, the lid member 1023 and the cup body member 1024 may each becomprised of rubber (including neoprene), metal, wood, paper, ceramic,glass, or rigid or semi-rigid polymer materials, such as polypropylene,polyvinyl chloride, silicone, silicone blends, or other polymers orcombinations of all such polymers. It is to be noted that in variousembodiments, the lid member 1023 and the cup body member 1024 may beconstructed in whole or in part of gas-permeable materials, allowinglimited amounts of oxygen to penetrate the lid member 1023 and the cupbody member 1024 so that the portion of the body under the cover 1020 inthe area of the wound 1015 can “breathe.” In some embodiments, allportions of the top cup member 1021 are preferably constructed of onetype of semi-rigid material, such as polypropylene. In otherembodiments, the top cup member 1021 may be constructed of more than onematerial. For example, the lid member 1023 may be constructed ofsilicone and the cup body member 1024 of the cover 1020 may be comprisedof polyvinyl chloride, so that the lid member 1023 may be stretchedenough to overlap and seal against the outer edge of the cup body member1024 to form an operable seal, as described in more detail below. Thepreferred wall thickness of the cover 1020 and its various componentparts is dependent upon the size and shape of the cover 1020, the size,shape and contour of the portion of the body to be covered by the cover1020, the magnitude of the reduced pressure to be maintained under thecover 1020, the materials comprising the cover 1020, and the individualpreferences of the user of the cover 1020. For example, in theembodiment of the cover 1020 illustrated in FIG. 7, for a top cup member1021 constructed entirely of a silicone blend and having an approximatediameter of 4 inches and an approximate height of 3 inches, thepreferred wall thickness of the top cup member 1021 is in the range from1/32 inches to ⅜ inches. It is to be noted that in other embodiments thewall thickness of the various portions of the top cup member 1021 mayvary from embodiment to embodiment, as well as from portion to portionof the top cup member 1021. Generally, the top cup member 1021 of theillustrated embodiment may be constructed using any suitable meanscurrently known in the art or that may be developed in the art in thefuture. For example, a top cup member 1021 constructed entirely of asilicone blend may be manufactured by means of injection molding. Asanother example, embodiments of covers 1020 constructed of differenttypes of materials may be constructed in the manner described above inthis paragraph. It is to be noted that embodiments of the top cup member10121 comprised of one piece, without separate lid member and cup bodymember as illustrated by the cover 10120 of FIG. 11, the top cup membermay be constructed of substantially the same materials, have the samewall thicknesses, and be constructed in substantially the same manner asdescribed above in this paragraph.

In some embodiments of the present invention, as illustrated in FIG. 7,the cover 1020 further comprises a port 1025. The port 1025 is adaptedto be of a size and shape so that the reduced pressure supply means maybe operably connected to the top cup member 1021 by means of the port1025. When the port 1025 is operably connected to the reduced pressuresupply means, reduced pressure may be supplied to the volume under thecover 1020 at the site of the wound 1015 to be treated. Although theport 1025 is positioned at a location near one side of the lid member1023 of the enclosure 1020 in the embodiment illustrated in FIG. 7, theport 1025 may be located at other positions on the top cup member 1021(on either the lid member 1023 or the cup body member 1024) in otherembodiments, as long as the port 1025 does not adversely affect theability of the cup body member 1024 to form an operable seal with thelid member 1023 or the interface member 1022, as described in moredetail below. Although the port 1025 may be constructed of a materialdifferent from the material comprising the remainder of the top cupmember 1021 in various embodiments of the invention, the port 1025 ispreferably constructed from the same material comprising the top cupmember 1021 of the cover 1020. In the embodiment of the cover 1020illustrated in FIG. 7, the port 1025 is generally cylindrical in shapeand is further comprised of an approximately cylindrical channel 1025 athat extends from the top of the port 1025 to the bottom of the port1025. The port 1025 of this embodiment is thus able to receive a vacuumsystem or reduced pressure supply means, which are described in moredetail below, adapted to be connected to this shape of port 1025 andchannel 1025 a. In other embodiments of the invention, the port 1025 orthe channel 1025 a or both may have different shapes and configurationsas may be desired to adapt and connect the port 1025 and the channel1025 a to the vacuum system or reduced pressure supply means, which aredescribed in more detail below. In some of the embodiments comprising aport 10125, as illustrated in the embodiment of the cover 10120 of FIG.11, the top cup member 10121 may be further comprised of flow shutoffmeans (a one-way valve 10129 in this embodiment), which are operablyconnected to the port 10125 and described in more detail below.Referring again to FIG. 7 as an example, in other embodiments, a meansof connecting the top cup member 1021 to the reduced pressure supplymeans (described in more detail below) may be located on the top cupmember 1021 in lieu of or in conjunction with the port 1025. Forexample, in some embodiments, the port 1025 may be combined with avariable descending diameter adapter (commonly referred to as a“Christmas tree” adapter), a luer lock fitting, or other similar adapteror fitting.

In the embodiment of the cover 1020 illustrated in FIG. 7, the interfacemember 1022 is removably attached to the cup body member 1024 by theinterface attachment means (described in more detail below), which areused to make an approximately airtight and liquid-tight seal with thetop cup member 1021. In the illustrated embodiment, the interface member1022 is comprised of a border portion 1026, a membrane portion 1027, andmembrane flow control means, which are described in more detail below.The membrane portion 1027 in the illustrated embodiment has anapproximately flat surface and is approximately circular in shape whenviewed from above. In other embodiments, the membrane portion 1027 mayhave other shapes. For example, the surface of the membrane portion 1027may have a curved surface, so that it is concave (similar to a concavelens) in shape. In addition, the interface member 1022 (and its borderportion 1026 and membrane portion 1027) may be of almost any shape andsize, as long as the interface member 1022 is of a size and shapeadapted so that it fits against a portion of the surface of the top cupmember 1021 in a manner so that an approximately airtight andliquid-tight seal is maintained by the interface attachment means, asdescribed in more detail below. For example, when viewed from above, theinterface member 1022 may have an approximately elliptical, square,rectangular, polygonal, arcuate or other shape or combination of allsuch shapes. As another example, as illustrated in the embodiment of theinterface member 1022 a of the cover 1020 a illustrated in FIG. 8B, whenviewed from the side, the interface member 1022 a may appear to have anapproximately curved surface so that it may rest on portions of the bodythat have an approximately curved surface. Thus, in the illustratedembodiment, the border portion 1026 a has a generally flat top surfaceand an approximately concave lower surface bounding the membrane portion1027 a. Also in this embodiment, the interface member 1022 a isremovably attached to the cup body portion 1024 a of the top cup member1021 a using the interface attachment means, which are described in moredetail below. It is to be noted that in some embodiments, as illustratedby the embodiment of the cover 10120 in FIG. 11, the top surface of theborder portion 10126 of the interface member 10122 may be positionedadjacent to the bottom surface of the top cup member 10121. Thepreferred shape and size of the interface member 1022, 1022 a, 10122, aswell as the size and shape of the border portion 1026, 1026 a, 10126 andmembrane portion 1027, 1027 a, 10127 comprising it, are dependent uponthe size and shape of the top cup member 1021, 1021 a, 10121, materialscomprising the cover 1020, 10120, the thickness of the interface member1022,10 22 a, 10122, the nature of the wound to be treated, the size,shape and contour of the portion of the body to be covered by the cover1020, 1020 a, 10120, the magnitude of the reduced pressure to bemaintained under the cover 1020, 1020 a, 10120, the individualpreferences of the user of the cover 1020, 1020 a, 10120, and otherfactors related to the sealing means and interface attachment means, asdescribed in more detail below.

In the embodiment of the present invention illustrated in FIG. 7, theborder portion 1026 is constructed of a material that is rigid enough tosupport the interface member 1022 and the cover 1020 away from thewound. Thus, the border portion 1026 of the cover 1020 may be comprisedof almost any rigid or semi-rigid medical grade material that iscurrently known in the art or that may be developed in the art in thefuture, as long as such material is liquid-impermeable, suitable forpurposes of wound treatment (e.g., can be sterilized and does not absorbsignificant amounts of fluids, such as wound exudate), and is capable ofsupporting the cover 1020 away from the wound. For example, the borderportion 1026 may be comprised of rubber (including neoprene), metal,wood, paper, ceramic, glass, or rigid or semi-rigid polymer materials,such as polypropylene, polyvinyl chloride, silicone, silicone blends, orother polymers or combinations of all such polymers. In the illustratedembodiment, the membrane portion 1027 is constructed of a material thatis strong enough to support the membrane flow control means, which aredescribed in more detail below. Thus, the membrane portion 1027 of thecover 1020 may be comprised of almost any rigid, semi-rigid, or flexiblemedical grade material that is currently known in the art or that may bedeveloped in the art in the future, as long as such material isliquid-impermeable, suitable for purposes of wound treatment (e.g., canbe sterilized and does not absorb significant amounts of fluids, such aswound exudate), and is capable of supporting the membrane flow controlmeans, which are described in more detail below. For example, themembrane portion 1027 may be comprised of rubber (including neoprene),metal, wood, paper, ceramic, glass, or rigid or semi-rigid polymermaterials, such as polypropylene, polyvinyl chloride, silicone, siliconeblends, or other polymers or combinations of all such polymers. It is tobe noted that in various embodiments, the interface member 1022 may beconstructed in whole or in part of gas-permeable materials, allowinglimited amounts of oxygen to penetrate the interface member 1022 so thatthe portion of the body under the cover 1020 can “breathe.” In someembodiments, all portions of the interface member 1022 are preferablyconstructed of one type of semi-rigid material, such as polypropylene.In other embodiments, the interface member 1022 may be constructed ofmore than one material. For example, the membrane portion 1027 may beconstructed of silicone and the border portion 1026 of the cover 1020may be comprised of polyvinyl chloride, so that the membrane portion1027 may be more flexible than the border portion 1026. The preferredwall thickness of the interface member 1022 and its various componentparts is generally dependent upon the same parameters as described abovefor the top cup member 1021. Although the interface member 1022 need notbe constructed of the same materials as the top cup member 1021, it ispreferred that the interface member 1022 be constructed of the samematerials as the top cup member 1021. Generally, the interface member1022 of the illustrated embodiment may be constructed using any suitablemeans currently known in the art or that may be developed in the art inthe future. For example, an interface member 1022 constructed entirelyof one material may be manufactured by means of injection molding. Asanother example, the component parts of an interface member 1022constructed of different types of materials may be attached together byany appropriate means, such as by welding, fusing, adhesives, glues,bolts, screws, pins, rivets, clamps, or other fasteners or other meansor combinations of all such means.

Referring to the embodiment of the cover 1020 illustrated in FIG. 7, theinterface member 1022 is further comprised of membrane flow controlmeans, which allow exudate aspirated from the wound 1015 to flow intothe volume of the top cup member 1021, but not in the oppositedirection. In the illustrated embodiment, the membrane flow controlmeans is comprised of eight flow control valves 1028. It is to be notedthat in various embodiments the flow control valves 1028 may be any typeof valve currently known in the relevant art or that may be developed inthe relevant art in the future that is suitable for operation in reducedpressure environments that allows fluids to flow in one directionthrough the valve, but not in the opposite direction. For example, suchvalves 1028 may generally be comprised of sprung or unsprung flapper ordisc-type valves. In the illustrated environment, the flow controlvalves 1028 are comprised of flapper-type valves, which are each furthercomprised of two flappers that are approximately semi-circular in shapeand hinged at their outside edge so that when they fall together theyform a seal that only allows fluids to flow in one direction (from thewound 1015 to the volume within the top cup member 1021 in thisembodiment). Although the interface member 1022 may have at least oneflow control valve 1028 in some embodiments, the interface member 1022may have almost any number of flow control valves 1028 in otherembodiments. For example, as illustrated in FIG. 11, the interfacemember 10122 may be comprised of two flow control valves 10128. Inembodiments of the present invention comprising flow control valves1028, the preferred number and type of valves 1028 is dependent upon theshape and size of the interface member 1022, the materials comprisingthe interface member 1022, the thickness of the membrane portion 1027,the nature of the wound 1015 to be treated, the amount of exudateanticipated, the size, shape and contour of the portion of the body tobe covered by the cover 1020, the magnitude of the reduced pressure tobe maintained under the cover 1020, the individual preferences of theuser of the cover 1020, and other factors related to the sealing means,as described in more detail below. It is to be noted that in someembodiments, the flow control valves 1028 may be formed from a singlepiece with the membrane portion 1027, or may be attached to the membraneportion 1027 using any suitable means, such as by welding, fusing,adhesives, glues, bolts, screws, pins, rivets, clamps, or otherfasteners or means or combinations of all such means. In otherembodiments, the membrane flow control means may be comprised of amembrane portion 1027 that is constructed in whole or in part of amaterial that allows fluids to flow in one direction, but not in theopposite direction. In these embodiments, exudate from the wound 1015flows from the wound 1015 through the membrane portion 1027 (or aportion thereof) to the volume within the top cup member 1021, but doesnot flow in the reverse direction back to the wound 1015.

In various embodiments, the interface attachment means, which may beused to removably or permanently attach the interface member 1022 to thetop cup member 1021, may be any suitable means currently known in therelevant art or developed in the relevant art in the future that may beused to create an airtight and liquid-tight seal (sometimes referred toherein as an “operable seal”) between the interface member 1022 and thetop cup member 1021. For example, in the embodiment illustrated in FIG.9, which is an enlarged cross-sectional elevation view of an interfaceattachment means, the border portion 1026 b is constructed of asemi-rigid material (such as silicone) and has a lip portion 1026 b′that extends around the perimeter of the interface member 1022 b. Thecup body member 1024 b of the top cup member 1021 b also has a lipportion 1024 b′ adjacent to the bottom edge of the cup body member 1024b that extends around the perimeter of the bottom edge of the cup bodymember 1024 b. In this embodiment, the interface attachment means iscomprised of the lip portion 1026 b′ of the interface member 1022 bbeing stretched over the lip portion 1024 b′ of the top cup member 1021,so that the lip portions are joined tightly together to form an operableseal. As another example, as illustrated in FIG. 10, the interfaceattachment means may be comprised of an o-ring (or gasket or similarsealing means) 1026 c′ that is positioned in a groove extending aroundthe perimeter of the border portion 1026 c or the cup body member 1024 cor both, so that the o-ring 1026 c′ forms an operable seal between thetop cup member 1021 c and the interface member 1022 c. Referring againto FIG. 7 as an example, in still other embodiments, the exterior bottomportion of the cup body member 1024 may be threaded and the interiorbottom portion of the border portion 1026 of the interface member 1022may be of a structure to receive such threads, so that an operable sealis created when the cup body member 1024 is screwed into the interfacemember 1022. In yet other embodiments, as illustrated in FIG. 11, theinterface attachment means may be comprised of a magnetic strip (notshown) attached to the bottom surface 10124 a of the cup body member10124 of the top cup member 10121 and to the top surface 10126 a of theborder portion 10126 of the interface member 10122, so that suchsurfaces abut against one another in the manner illustrated in FIG. 11when the surfaces are attracted by magnetic force, creating an operableseal. Further, the interface attachment means may be comprised of awasher, gasket, o-ring or similar structure (not shown) attached to thebottom surface 10124 a of the cup body member 10124 of the top cupmember 10121 or to the top surface 10126 a of the border portion 10126of the interface member 10121, or both, so that such surfaces abutagainst one another in the manner illustrated in FIG. 11, creating anoperable seal. In these embodiments, the top cup member 10121 may beheld in place against the interface member 10122 by means of clips,brackets, pins, clamps, clasps, adhesives, adhesive tapes, quick-releaseor other fasteners, or combinations of such means. In addition, manytypes of sealing means that may be used to removably attach componentsof kitchenware-type items together may by used as the interfaceattachment means. It is also to be noted that in other embodiments theinterface attachment means may be comprised of means to permanentlyattach the interface member 1022 to the top cup member 1021 or offorming the interface member 1022 and the top cup member 1021 as asingle piece. In these embodiments, and referring to the cover 1020 ofFIG. 7 as an example, the interface member 1022 and the top cup member1021 may be fabricated as a single piece, such as by injection molding,or they may be attached together by any appropriate means, such as bywelding, fusing, adhesives, glues, bolts, screws, pins, rivets, clamps,or other fasteners or means or any combinations of all such means.Referring again to FIG. 7 as an example, it is to be noted that the lidattachment means that may be used to removably or permanently attach thelid member 1023 to the cup body member 1021 may have substantially thesame structure, features, characteristics and operation as any or all ofthe embodiments comprising the interface attachment means describedabove.

Another embodiment of the present invention is the treatment appliance10110 illustrated in FIG. 11. In this embodiment, the treatmentappliance 10110 is comprised of a treatment device 10111 and a vacuumsystem, generally designated 10150, which is operably connected to, andprovides a supply of reduced pressure to, the treatment device 10111.Also in this embodiment, the treatment device 10111 is comprised of acover 10120. In addition, in this embodiment, the vacuum system 10150 isfurther comprised of a reduced pressure supply source, generallydesignated 10130, which is illustrated schematically and described inmore detail below, and reduced pressure supply means, generallydesignated 10140, which are described in more detail below. Also in thisembodiment, the reduced pressure supply means 10140 are used to connectthe reduced pressure supply source 10130 to the cover 10120 in a mannerso that reduced pressure is supplied to the volume under the cover 10120at the site of the wound 10115 to be treated, as described in moredetail below. In the embodiment illustrated in FIG. 11, the illustratedcover 10120 is comprised of a top cup member 10121, an interface member10122, and interface attachment means to removably attach the top cupmember 10121 to the interface member 10122. In the illustratedembodiment, the interface attachment means is comprised of a magneticstrip (not shown) on the top surface 10126 a of the border portion 10126of the interface member 10122 and a magnetic strip (not shown) on thebottom surface 10124 a of the cup body member 10124 of the top cupmember 10121. An operable seal is formed between the interface member10122 and the top cup member 10121 by the magnetic attraction of themagnetic strips. In other embodiments, the interface attachment meansmay be comprised of any of the interface attachment means of theembodiment illustrated and described above in connection with FIG. 7through FIG. 11. Alternatively, the interface member 10122 and the topcup member 10121 may be formed as a single piece or permanentlyattached, as illustrated and described above in connection with FIG. 7through FIG. 11. It is to be noted that in this and other embodiments ofthe invention, the cover 10120 may have substantially the samestructure, features, characteristics, and operation as any embodiment ofany of the covers 1020, 1020 a, 10120 of the embodiments described aboveand illustrated in connection with FIG. 7 through FIG. 11. It is also tobe noted that in other embodiments of the present invention, the top cupmember 10121 may be used for treatment of a wound 10115 without theinterface member 10126. In these embodiments, the top cup member 10121alone is placed over the wound 10115 and reduced pressure is applied tothe volume under the top cup member 10121.

In various embodiments of the present invention, as illustrated in FIG.11, the interface member 10122 of the cover 10120 may be comprised of asemi-rigid material and the sealing means may be comprised of thesuction of the interface member 10122 against the portion 10116 of thebody adjacent to the interface member 10122 of the cover 10120, suchsuction being produced by the presence of reduced pressure in the volumeunder the cover 10120 at the site of the wound 10115. In otherembodiments, the sealing means may be comprised of an adhesive, anadhesive tape, lanolin, or other sealant, or any combination of suchmeans, that is disposed between the interface member 10122 and theportion 10116 of the body adjacent to the interface member 10122 ordisposed over the interface member 10122 and the portion of the bodyoutside the perimeter of the interface member 10122. In yet otherembodiments, the sealing means may be comprised of a material (notillustrated) that is positioned approximately over the cover 10120 andwrapped around the portion 10116 of the body on which the cover 10120 ispositioned. This material is used to hold the cover 10120 against theadjacent portion 10116 of the body. For example, if the wound 10115 wereon the patient's leg, an elastic bandage or adhesive tape may be wrappedover the cover 10120 and around the leg.

In the embodiment illustrated in FIG. 11, the reduced pressure supplysource 10130 of the vacuum system 10150, which produces a source ofreduced pressure or suction that is supplied to the cover 10120, iscomprised of a vacuum pump 10131, a control device 10132, and a filter10133. Although the preferred means of producing the reduced pressure orsuction is a vacuum pump 10131 in this embodiment, in other embodimentsof the invention, other means may be used, such as an outlet port of acentralized hospital vacuum system. In the illustrated embodiment,predetermined amounts of suction or reduced pressure are produced by thevacuum pump 10131. The vacuum pump 10131 is preferably controlled by acontrol device 10132, such as a switch or a timer that may be set toprovide cyclic on/off operation of the vacuum pump 10131 according touser-selected intervals. Alternatively, the vacuum pump 10131 may beoperated continuously without the use of a cyclical timer. In addition,in some embodiments the control device 10132 may provide for separatecontrol of the level of reduced pressure applied to the volume under thecover 10120 at the site of the wound 10115 and the flow rate of fluidaspirated from the wound 10115, if any. In these embodiments, relativelylow levels of reduced pressure may be maintained at the site of thewound 10115 in the volume under the treatment device 10111, while stillproviding for the removal of a relatively large volume of exudate fromthe wound 10115. A filter 10133, such as a micropore filter, ispreferably attached to the inlet of the vacuum pump 10131 to preventpotentially pathogenic microbes or aerosols from contaminating, and thenbeing vented to atmosphere by, the vacuum pump 10131. In otherembodiments, the filter 10133 may also be a hydrophobic filter thatprevents any exudate from the wound 10115 from contaminating, and thenbeing vented to atmosphere by, the vacuum pump 10131. It is to be notedthat in other embodiments of the invention, the reduced pressure supplysource 10130 may not have a filter 10133 or a control 10132 or anycombination of the same.

In other embodiments of the invention, the reduced pressure supplysource 10130 of the vacuum system 10150, may be comprised of a small,portable vacuum pump 10131. In some of these embodiments, a filter 10133or a power source (not illustrated), or both, may also be containedwithin the housing for the portable vacuum pump 10131. In theseembodiments, the portable vacuum pump 10131 is preferably controlled bya control device 10132 that is also located within the housing for theportable vacuum pump 10131, which may provide substantially the samefunctions as the control device 10132 described above. Except for itssmaller size, the portable vacuum pump 10131 may operate insubstantially the same manner as the vacuum pump 10131 described above.Also, in these embodiments, the filter 10133 may have the samestructure, features, characteristics, and operation, and providesubstantially the same functions, as the filter 10133 described above.In some of these embodiments, the filter 10133 may be rigidly connectedto the portable vacuum pump 10131. The power source may be any source ofenergy currently known in the art or that may be developed in the art inthe future that may be used to power the portable vacuum pump 10131. Forexample, in some embodiments, the power source may be a fuel cell,battery or connection to a standard wall electrical outlet.

In the embodiment of the invention illustrated in FIG. 11, the reducedpressure supply means 10140 of the vacuum system 10150, which are usedto connect the reduced pressure supply source 10130 to the cover 10120so that reduced pressure is supplied to the volume under the cover 10120at the site of the wound 10115, is comprised of at least one tubingmember 10141. In this embodiment, the at least one tubing member 10141is sufficiently flexible to permit movement of the at least one tubingmember 10141, but is sufficiently rigid to resist constriction whenreduced pressure is supplied to the cover 10120 or when the location ofthe wound 10115 is such that the patient must sit or lie upon the atleast one tubing member 10141 or upon the treatment device 10111. In theembodiment illustrated in FIG. 11, the at least one tubing member 10141is connected to the cover 10120 by inserting one end of the at least onetubing member 10141 into an opening 10125 a of a port 10125 of the cover10120. In this embodiment, the at least one tubing member 10141 is heldin place in the opening 10125 a by means of an adhesive. It is to benoted that in other embodiments of the invention, the at least onetubing member 10141 may be connected to the port 10125 of the cover10120 using any suitable means currently known in the art or developedin the art in the future. Examples include variable descending diameteradapters (commonly referred to as “Christmas tree” adapters), luer lockfittings and adapters, clamps, and combinations of such means.Alternatively, the port 10125 and the at least one tubing member 10141may be fabricated as a single piece. Similar means may be used toconnect the other end of the at least one tubing member 10141 to thevacuum pump 10131 or other reduced pressure supply source 10130providing the reduced pressure.

In the embodiment of the present invention illustrated in FIG. 11, thetreatment device 10111 functions to actively draw fluid or exudate fromthe wound 10115 through two flow control valves 10128 positioned on themembrane portion 10127 of the interface member 10122 into the interiorvolume of the cover 10120. In this embodiment, it is generally desirableto collect exudate in the interior volume of the cover 10120, but not toallow the exudate to flow into the reduced pressure supply means 10140in order to prevent clogging of the vacuum pump 10131. In addition, itis desirable to halt or inhibit the supply of reduced pressure to thecover 10120 in the event that the exudate aspirated from the wound 10115exceeds a predetermined quantity. Further, it is desirable to interruptthe application of suction to the cover 10120 to prevent exsanguinationin the unlikely event a blood vessel ruptures under the cover 10120during treatment. If, for example, a blood vessel ruptures in thevicinity of the cover 10120, a shutoff mechanism would be useful toprevent the vacuum system 10150 from aspirating any significant quantityof blood from the patient. As a result, the top cup member 10121 in theillustrated embodiment is further comprised of flow shutoff means. Inthis embodiment, the flow shutoff means is comprised of a flapper-typevalve 10129, which is generally comprised of a flapper 10129 a that ishinged to an interior surface of the port 10125 and seats against a stop10129 b. The flapper 10129 a is buoyant when compared to the exudate, sothat it floats upon the exudate as the level of exudate in the volume ofthe cover 10120 rises to the level of the flapper valve 10129. Theflapper 10129 a is, however, heavy enough not to be drawn against thestop 10129 b when reduced pressure is applied to the cover 10120 by thevacuum system 10150. Thus, as the exudate level rises to the level ofthe stop 10129 b, the flapper 10129 a floats upon the exudate until theflapper 10129 a seats against the stop 10129 b, which seals the cover10120 so that reduced pressure is no longer supplied to the cover 10120by the vacuum system 10150. In other embodiments, the flow shutoff meansmay be comprised of almost any other type of shutoff valve currentlyknown in the relevant art or that may be developed in the relevant artin the future that is suitable for this purpose and use in a reducedpressure environment. Another example of such valve is a float valve,wherein a float ball floats upon the exudate so that the float ballseals against a seat when the level of exudate reaches a predeterminedlevel. All such valves are well known in the relevant art. In otherembodiments, other types of mechanisms may also be employed to detectthe liquid level within the cover 10120 in order to arrest operation ofthe vacuum system 10150. In addition, in various embodiments of theinvention, the flow shutoff means may be comprised of any means thatenables the vacuum system 10150 to halt the supply of reduced pressureto the cover 10120 at any time that the volume of exudate from the wound10115 exceeds a predetermined amount. Such means may include mechanicalswitches, electrical switches operably connected to the vacuum systemcontroller 10132, optical, thermal or weight sensors operably connectedto the vacuum system controller 10132, and any other means that arecurrently known in the relevant art or that may be developed in therelevant art in the future.

In some embodiments of the invention, the treatment device 10111 furthercomprises tissue protection means (not illustrated) to protect andstrengthen the surface tissue of the portions 10116 of the body that areadjacent to the cover 10120. The tissue protection means protects suchtissue by preventing abrasion and maceration of the tissue. Preferably,the tissue protection means is a hydrocolloid material, such as COLOPASTHydrocolloid 2655 anhydrous lanolin, or any combination of suchhydrocolloid materials. More preferably, the tissue protection means isCOLOPAST Hydrocolloid 2655. The tissue protection means may be appliedto the body tissue to be protected, or it may be applied to the surfaceof the cover 10120 that is to be in contact with the body tissue 10116,or both, prior to placing the cover 10120 over the wound 10115. It is tobe noted that application of the tissue protection means to the bodytissue 10116 that is adjacent to the cover 10120 at the site of thewound 10115 may only entail application of the tissue protection meansto the parts of the body tissue 10116 adjacent to the cover 10120 thatrequire such protection.

Referring to FIG. 11, a method of using the treatment appliance 10110 ofthe illustrated embodiment is also disclosed. In this example, the cover10120 is removed from an aseptic package in which it is stored. Thevarious component parts of the cover are operably sealed together. Forexample, in the illustrated embodiment, the top cup member 10121 isoperably sealed to the interface member 10122. In embodiments where thetop cup member 1021 further comprises a lid member 1023 and a cup bodymember 1024, as illustrated in FIG. 7, the lid member 1023 and the cupbody member 1024 are also operably sealed together. Referring again toFIG. 11, this sealing of the component parts of the cover 10120 mayoccur before, during or after the cover 10120 is placed over the wound10115. The cover 10120 is placed over and encloses the wound 10115. Thecover 10120 is connected to the vacuum system 10150 by means of the port10125 on the cover 10120 either before, after or during the placement ofthe cover 10120 over the wound 10115. Where it is deemed necessary bythe user of the treatment appliance 10110, tissue protection means, asdescribed above, may be placed on a portion of the cover 10120, on thebody tissue to be protected, or both, prior to placing the cover 10120over the wound 10115. Reduced pressure is then supplied to the cover10120 by the vacuum system 10150. In the illustrated embodiment, whenreduced pressure is applied to the volume under the cover 10120 at thesite of the wound 10115, the cover 10120 is drawn downward by thereduced pressure so that the cover 10120 is drawn tightly against thesurface of the adjacent portion 10116 of the body, thus forming anoperable seal between the cover 10120 and the portion 10116 of the bodyadjacent to the cover 10120. References to an “operable seal” and“sealing means” herein refer generally to a seal that may be madegas-tight and liquid-tight for purposes of the reduced pressuretreatment of the wound 10115. It is to be noted that this seal need notbe entirely gas-tight and liquid-tight. For example, the operable sealmay allow for a relatively small degree of leakage, so that outside airmay enter the volume under the cover 10120 at the site of the wound10115, as long as the degree of leakage is small enough so that thevacuum system 10150 can maintain the desired degree of reduced pressurein the volume under the cover 10120 at the site of the wound 10115. Asanother example, the operable seal formed by the cover 10120 may not besolely capable of maintaining the reduced pressure in the volume underthe cover 10120 at the site of the wound 10115 due to the shape of thebody portion 10116 at the site of the wound 10115, due to theorientation of the wound 10115, or due to some other reason. In thesecases, as well as other cases, it may be necessary or desirable toprovide other sealing means (not illustrated), which are described inmore detail above. In some embodiments of the present inventioncomprising a lid member 1023, as illustrated by the cover 1020 of FIG.7, the method may also comprise one or more of the steps of halting theapplication of reduced pressure to the cover 1020, removing the lidmember 1023 from the cup body member 1024, attending to the wound 10115,re-attaching the lid member 1023 to the cup body member 1024, and thenreapplying reduced pressure to the volume under the cover 1020 in thearea of the wound 10115. In yet other embodiments, and referring againto FIG. 11, the method may comprise one or more of the steps ofmonitoring the fluid level 10117 in the volume within the cover 10120,halting the application of reduced pressure to the cover 10120 when thefluid level 10117 reaches a predetermined level, removing the fluid inthe volume within the cover 10120, and reapplying reduced pressure tothe volume under the cover 1020 in the area of the wound 10115. In someembodiments of the invention, the reduced pressure maintained in thevolume under the cover 10120 at the site of the wound 10115 is in therange from approximately 20 mm of Hg below atmospheric pressure toapproximately 125 mm of Hg below atmospheric pressure. In yet otherembodiments, the reduced pressure is applied to the cover 10120 in acyclic nature, the cyclic nature providing alternating time periods ofapplication of reduced pressure and non-application of reduced pressure.In various embodiments, the method also comprises the step ofmaintaining reduced pressure in the volume under the cover 10120 at thesite of the wound 10115 until the wound 10115 has progressed toward aselected stage of healing.

Another embodiment of the invention is the treatment appliance 10210illustrated in FIG. 12. In this embodiment, the treatment appliance10210 is comprised of a treatment device 10211 and a vacuum system,generally designated 10250, operably connected to, and providing asupply of reduced pressure to, the treatment device 10211. In addition,in this embodiment, the vacuum system 10250 is further comprised of areduced pressure supply source, generally designated 10260, which isdescribed in more detail below, and reduced pressure supply means 10240,which are described in more detail below. Also in this embodiment, thetreatment device 10211 is further comprised of a cover 10220, whichgenerally has substantially the same structure, features, andcharacteristics as the embodiment of the cover 10120 illustrated anddescribed above in connection with FIG. 11. It is to be noted, however,that in other embodiments of the invention, the cover 10220 may havesubstantially the same structure, features, characteristics, andoperation as any embodiment of all of the covers 1020, 1020 a, 10120 ofthe embodiments of the invention described above and illustrated inconnection with FIG. 7 through FIG. 11. In the embodiment illustrated inFIG. 12, the cover 10220 is placed over and encloses a wound 10215. Inthe illustrated embodiment, the cover 10220 may be sealed to theadjacent portions 10216 of the body using any of the sealing means oroperable seals described above and illustrated in connection with FIG.11.

In the embodiment of the invention illustrated in FIG. 12, the vacuumsystem 10250 is generally comprised of a suction bulb 10261 having aninlet port 10262 and an outlet port 10263, a bulb connection tubingmember 10264, an exhaust tubing member 10265, an exhaust control valve10266, a filter 10267, and a supplemental vacuum system (illustratedschematically and generally designated 10250 a). In this embodiment, thesuction bulb 10261 is a hollow sphere that may be used to produce asupply of reduced pressure for use with the treatment device 10211. Inaddition, in some embodiments, the suction bulb 10261 may also be usedto receive and store exudate aspirated from the wound 10215. The inletport 10262 of the suction bulb 10261 is connected to one end of the bulbconnection tubing member 10264, which is connected to the reducedpressure supply means 10240, a tubing member in this embodiment, bymeans of a connector 10246. The connection tubing member 10264 isconnected to the reduced pressure supply means 10240 in a manner so thatthe interior volume of the suction bulb 10261 is in fluid communicationwith the volume under the cover 10220 in the area of the wound 10215. Inthis embodiment, the bulb connection tubing member 10264 and the reducedpressure supply means 10240 are sufficiently flexible to permit movementof the bulb connection tubing member 10264 and the reduced pressuresupply means 10240, respectively, but are sufficiently rigid to resistconstriction when reduced pressure is supplied to the cover 10220 orwhen the location of the wound 10215 is such that the patient must sitor lie upon the bulb connection tubing member 10264, upon the reducedpressure supply means 10240, or upon the treatment device 10311. Theoutlet port 10263 of the suction bulb 10261 is connected to the exhausttubing member 10265. In this embodiment, the exhaust tubing member 10265is sufficiently flexible to permit movement of the exhaust tubing member10265, but is sufficiently rigid to resist constriction when reducedpressure is supplied to the cover 10220. The inlet port 10262 of thesuction bulb 10261 may be connected to the bulb connection tubing member10264 and the outlet port 10263 of the suction bulb 10261 may beconnected to the exhaust tubing member 10265 using any suitable means,such as by welding, fusing, adhesives, clamps, or any combination ofsuch means. In addition, in some embodiments, the suction bulb 10261,the bulb connection tubing member 10264, and the exhaust tubing member10265 may be fabricated as a single piece. In the illustratedembodiment, the exhaust control valve 10266 and the filter 10267 areoperably connected to the exhaust tubing member 10265. In thisembodiment, the exhaust control valve 10266 is used to regulate the flowof fluids (gases and liquids) to and from the suction bulb 10261 and thesupplemental vacuum system 10250 a. In embodiments of the invention thatdo not have a supplemental vacuum system 10250 a, the exhaust controlvalve 10266 regulates flow of fluids to and from the suction bulb 10261and the outside atmosphere. Generally, the exhaust control valve 10266allows fluids to flow out of the suction bulb 10261 through the outletport 10263, but not to flow in the reverse direction unless permitted bythe user of the appliance 10210. Any type of flow control valve may beused as the exhaust control valve 10266, as long as the valve 10266 iscapable of operating in the anticipated environment involving reducedpressure and wound 10215 exudate. Such valves are well known in therelevant art, such as sprung and unsprung flapper-type valves anddisc-type valves, operating in conjunction with or without ball, gateand other similar types of valves. In this embodiment, the filter 10267is operably attached to the exhaust tubing member 10265 between theoutlet port 10263 of the suction bulb 10261 and the exhaust controlvalve 10266. The filter 10267 prevents potentially pathogenic microbesor aerosols from contaminating the exhaust control valve 10266 (andsupplemental vacuum system 10250 a), and then being vented toatmosphere. The filter 10267 may be any suitable type of filter, such asa micropore filter. In other embodiments, the filter 10267 may also be ahydrophobic filter that prevents any exudate from the wound 10215 fromcontaminating the exhaust control valve 10266 (and the supplementalvacuum system 10250 a) and then being vented to atmosphere. In stillother embodiments, the filter 10267 may perform both functions. It is tobe noted, however, that the outlet port 10263, the exhaust control valve10266, the filter 10267, or any combination of the exhaust control valve10266 and the filter 10267, need not be utilized in connection with thevacuum system 10250 in other embodiments of the invention.

In some embodiments of the invention illustrated in FIG. 12 that do notutilize a supplemental vacuum system 10250 a, the suction bulb 10261 maybe used to produce a supply of reduced pressure in the following manner.First, the user of the appliance 10210 appropriately seals all of thecomponent parts of the appliance 10210 in the manner described herein.For example, the top cup member 10221 of the cover 10220 is operablysealed to the interface member 10222 of the cover 10220, and the cover10220 is placed over and encloses the wound 10215. At least a portion ofthe interface member 10222 is sealed (or placed adjacent) to theadjacent portions 10216 of the body, and the reduced pressure supplymeans 10240 is connected to the bulb connection tubing member 10264 bymeans of the connector 10246. The user then opens the exhaust controlvalve 10266 and applies force to the outside surface of the suction bulb10261, deforming it in a manner that causes its interior volume to bereduced. When the suction bulb 10261 is deformed, the gas in theinterior volume is expelled to atmosphere through the outlet port 10263,the exhaust tubing member 10265, the filter 10267, and the exhaustcontrol valve 10266. The user then closes the exhaust control valve10266 and releases the force on the suction bulb 10261. The suction bulb10261 then expands, drawing gas from the area of the wound 10215 underthe treatment device 10211 into the suction bulb 10261 and causing thepressure in such area to decrease. To release the reduced pressure, theuser of the appliance 10210 may open the exhaust control valve 10266,allowing atmospheric air into the interior volume of the suction bulb10261. The level of reduced pressure may also be regulated bymomentarily opening the exhaust control valve 10266.

The suction bulb 10261 may be constructed of almost any fluidimpermeable flexible or semi-rigid material that is suitable for medicaluse and that can be readily deformed by application of pressure to theoutside surface of the suction bulb 10261 by users of the appliance10210 and still return to its original shape upon release of thepressure. For example, the suction bulb 10261 may be constructed ofrubber, neoprene, silicone, or other flexible or semi-rigid polymers, orany combination of all such materials. In addition, the suction bulb10261 may be of almost any shape, such as cubical, ellipsoidal, orpolyhedral. The suction bulb 10261 may also be of varying size dependingupon the anticipated use of the suction bulb 10261, the size of thewound treatment device 10211, use of a supplemental vacuum system 10250a, the level of reduced pressure desired, and the preference of the userof the appliance 10210. In the embodiment of the invention illustratedin FIG. 12, the supplemental vacuum system 10250 a is connected to theexhaust tubing member 10265 and is used to provide a supplemental supplyof reduced pressure to the suction bulb 10261 and treatment device10211. In this embodiment, the supplemental vacuum system 10250 a mayhave substantially the same structure, features, characteristics andoperation of the various embodiments of the vacuum system 10250 of theinvention described above and illustrated in connection with FIG. 11. Itis to be noted, however, that the supplemental vacuum system 10250 aneed not be used in connection with the vacuum system 10250 in otherembodiments of the invention.

Except as illustrated and described above in connection with FIG. 12,the treatment appliance 10210 may generally be used in a manner similarto the treatment appliance 10110 described above and illustrated inconnection with FIG. 11. As a result, except as described herein, theexample of how the embodiment of the treatment appliance 10110 and thecover 10120 described above and illustrated in connection FIG. 11 may beused in treatment of a wound 10115 also applies to the embodiment of theappliance 10210 of the invention described above and illustrated inconnection with FIG. 12.

1. A wound therapy device, comprising: a cover layer configured forpositioning over a wound to create an area in which a reduced pressuremay be maintained over the wound; a port on the cover layer, the portdefining a fluid passage for fluid coupling with a reduced pressuresupply conduit; and a filter at the port and positioned relative to thefluid passage, the filter dimensioned to prevent passage of woundexudate through the fluid passage of the port.
 2. The wound therapydevice of claim 1, wherein the filter is within the port.
 3. The woundtherapy device of claim 1, wherein the cover layer is configured tocreate a collection chamber for collecting and storing wound fluids fromthe wound.
 4. The wound therapy device of claim 1, wherein the filter isconfigured to prevent passage of micro-organisms aspirated from thewound.
 5. The wound therapy device of claim 1, wherein the filter is amicropore filter.
 6. The wound therapy device of claim 1, wherein thefilter is a hydrophobic filter.
 7. The wound therapy device of claim 1,wherein the port includes: an outer surface and a patient surfacegenerally facing the wound, the fluid passage extending through theouter surface and the patient facing surface; and a connector segmentfor connection to the reduced pressure supply conduit.
 8. The woundtherapy device of claim 7, wherein the port is secured to the coverlayer.
 9. The wound therapy device of claim 1, further comprising anegative pressure source in fluid communication with the reducedpressure supply conduit.
 10. The wound therapy device of claim 1,wherein the filter comprises a therapeutic material, the therapeuticmaterial configured to control a characteristic of exudate drawn throughthe fluid passage of the portal member.
 11. The wound therapy device ofclaim 10, wherein the therapeutic material controls a bio-burden of theexudate.
 12. The wound therapy device of claim 1, wherein the filter isadapted to control one of aerosols and microbials.
 13. The wound therapydevice of claim 1, wherein the filter extends across the fluid passageof the port such that any fluid passing through the fluid passage of theport must pass through the filter.
 14. The wound therapy device of claim1, wherein the port includes an opening to receive a vacuum tube in areleasable and fluid tight manner.
 15. A wound therapy device,comprising: a cover positionable over a wound and configured to maintainreduced pressure under the cover at the site of the wound; a gasketpositionable around a perimeter of the wound; and a source of reducedpressure configured to provide reduced pressure to the cover so that thevolume under the cover at the site of the wound is supplied with reducedpressure; wherein the cover is removably attachable to the gasket toform an operable seal.
 16. The wound therapy device of claim 15, whereinthe gasket is configured to form part of a border around the wound,wherein in use the border is operably sealed to tissue of a patientsurrounding the wound.
 17. The wound therapy device of claim 15, whereinthe gasket is sealable relative to tissue of the patient surrounding thewound using an adhesive.
 18. The wound therapy device of claim 15,wherein the cover is removably attachable to the gasket with anadhesive.
 19. The wound therapy device of claim 15, further comprisingan interface member sized and configured to be placed in contact withthe tissue site.
 20. The wound therapy device of claim 19, wherein thegasket is attached to a border portion of the interface member.
 21. Areduced-pressure treatment system for treating a tissue site on apatient, the system comprising: an interface member sized and configuredto be placed in contact with the tissue site; a gasket positionablearound a perimeter of the tissue site; a cover positionable over theinterface member and releasably sealable to the gasket, wherein thecover is configured to create a sealed space between the cover and thetissue site; and a reduced-pressure source fluidly coupled to the sealedspace to deliver reduced pressure to the tissue site.
 22. Thereduced-pressure treatment system of claim 21, wherein the cover ispositioned over the interface member and is releasably sealed to thegasket by a first adhesive between the cover and the gasket.
 23. Thereduced-pressure treatment system of claim 22, wherein the gasket isreleasably attached around a perimeter of the tissue site, and whereinthe gasket has a first side and a second, patient-facing side.
 24. Thereduced-pressure treatment system of claim 22, wherein the gasket issecured relative to tissue of the patient surrounding the wound using asecond adhesive.
 25. The reduced-pressure treatment system of claim 23,wherein the gasket is sealed relative to tissue of the patientsurrounding the wound using a second adhesive between the second,patient-facing side of the gasket and the tissue of the patientsurrounding the wound.
 26. A method of treating a wound, comprising:positioning a gasket over tissue surrounding a wound; removably sealinga wound cover to the gasket to create a sealed space between the coverand the wound; and applying reduced pressure to the sealed space todeliver reduced pressure to the wound.